30 years of love and labor

This month, it is exactly 30 years ago that I started my first job as a researcher at the Department of Psychiatry at Utrecht University. It was June 1986. I had just graduated with an MSc in Clinical Psychology. Two months earlier, I had completed my 9-month clinical internship at a counseling center in Eugene, Oregon. Still ‘wet behind the ears’, I was accepted to conduct three years of research on panic disorder and agoraphobia in relation to the so-called hyperventilation syndrome, under the guidance of Drs. Bert Garssen and Floor Kraaimaat. The job market for clinical psychologists was extremely tight at the time. I felt fortunate to have gotten this research job. Dr. Kraaimaat also offered me the opportunity to be trained as a cognitive behavioral therapist, which I gladly accepted, although it meant basically working day and night. I would never leave the joint career path of scientist and practitioner.

Thirty years is a long time, and if I count the hours, I probably have worked about as many as I have spent sleeping, over the course of my life so far. Thinking back of those countless working hours, I remember the first manuscript I prepared for publication. It was a review paper in Dutch about the relevance of the therapist-client alliance for the effectiveness of psychotherapy. I worked long nights to process the feedback from the editor of the Dutch Journal of Psychotherapy who was quite meticulous; I believe there were ultimately three rounds of revisions, so my stamina was truly tested. This first experience would be the foreboding of a scientific writing career, in which every research paper, book chapter or review came under the scrutiny of my own and other scholars’ critical eye, within the system of academic peer review. I have now served in the role of journal reviewer and associated editor myself, thus demonstrating the beauty of academia: one generation teaches the next one the skills of research and academic writing, for free. In a world that has become so dominated by monetary value, I cherish the fact that academia still has these niches where goodness, truth and beauty prevail.

Tijdschrift voor Psychotherapie [Netherlands Journal of Psychotherapy], 13, 255-265.Psychotherapie artikel 1987

Reminiscing about three decades of labor, I feel blessed in so many ways. Yes, I worked hard, and sometimes too hard, but I was also given lots of opportunities by senior clinicians, researchers and managers in the field. I was asked to give workshops across the Netherlands and in many other countries, among them Finland and the USA. I met so many wonderful colleagues across the globe at the many different conferences and scientific meetings that I attended over the years. Many of these clinical and forensic psychologists have become friends, and we share holidays and family events whenever we can. The deep gratitude that comes with meeting like-minded professionals, who share similar interests and ideals, is one of the highlights of my working life.

I have about one decade to go before official retirement (for myself, I do not foresee an unofficial retirement). Sometimes I have been discouraged because of unfair sanctions of review boards and unbalanced media portrayals. But hey, shit happens. What keeps me going is when I get an e-mail from a former Greek student who says she’s so thankful for her training in our two-year Master’s program in Forensic Psychology, because she is using her knowledge and skills in her work at the Greek police now. What keeps me going is a letter from a prisoner, who is still grateful for the forensic mental health evaluation of him that I conducted 10 years ago. What keeps me going is a young professional who works at Veilig Thuis (Safe Home) who shares the positive effect on her work of an evidence-based interview method that we recently introduced. What keeps me going is the fact that I still observe so much misunderstanding and stigma surrounding mental health and substance use problems, domestic violence, and sexual violence (to name a few), that I believe we need to keep spreading evidence-science to the general public.


All of these work activities could not have been performed by me alone. All work is teamwork. To all my bright, dedicated and generous colleagues, I say thank you for 30 years of fulfilling labor, and I look forward to the next half:).









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Why we disagree with Brewin and Andrews

A plethora of research has shown that false memories can be elicited using various suggestive manipulations. Such false memories can be particularly dangerous in legal settings. And indeed: There are numerous cases in which innocent people were wrongfully convicted based on erroneous memories. But what is happening now? In a recent paper, Chris Brewin and Bernice Andrews want to make the case that “susceptibility to false memories of childhood events appears more limited than has been suggested”. Strong message, but we disagree. We were invited to write two commentaries on this review. They will soon be published but here they are already.

Commentary 1: (Authors: Henry Otgaar, Harald Merckelbach, Marko Jelicic, and Tom Smeets)

The Potential for False Memories is Bigger than Brewin and Andrews Suggest

Brewin and Andrews (in press; B&A) have taken up the challenge to provide a review on false memory susceptibility for childhood events. This is a daunting task as the psychological literature is replete with studies on false memories using different paradigms, different populations, and different ways of defining false memory. Although B&A are to be commended with executing such an arduous exercise, we disagree with their central message that “susceptibility to false memories of childhood events appears more limited than has been suggested” (p.1).

First, B&A’s review is selective in that it only focusses on a subset of studies employing imagination inflation, false feedback, and memory implantation to elicit false childhood memories. Moreover, B&A did not include literature on other false memory paradigms (e.g., misinformation, doctored video) that relate to autobiographical false memories and that have been informative regarding false memory propensity for childhood events. A case in point is their omission of several important imagination inflation studies; studies that have, for instance, looked at imagination inflation for action events (e.g., Goff & Roediger, 1998; Otgaar, Scoboria, Howe, Moldoveanu, & Smeets, in press). In contrast to what B&A argue, these studies did find that false memories were accompanied by high confidence. For example, Goff and Roediger (1998) stated “[t]he more errors [false memories] the subjects made, the higher their mean confidence ratings” (p.29).

One could argue that these studies did not tap into childhood events. However, imagination inflation studies on memory for actions typically involve multiple events that the participant either has to perform or imagine and these self-generated actions are – like childhood events –autobiographical in nature. If B&A had solely wanted to focus on studies concerning false memories for childhood events, then why did they include literature on the crashing memory paradigm (e.g., Smeets, Telgen, Ost, Jelicic, & Merckelbach, 2009)? This paradigm focuses on false memories for highly media-exposed, public events rather than childhood events. Likewise, B&A did not address studies on evidently wrong childhood memories, such as those of past lives (Peters, Horselenberg, Jelicic, & Merckelbach, 2007). Thus, it appears that B&A were rather selective in their inclusion of the extant literature, which makes their estimate of false memory vulnerability for childhood events provisional.

Second, a problematic selectivity also invaded B&A’s evaluation of studies that were included in their review. B&A argued that a full false memory is a memory that encompasses a belief in the occurrence of the event, recollective details, and high confidence that these details are accurate. They correctly showed that many false memory implantation studies did not measure confidence but then omitted such studies when they calculated their percentage of full false memory (15%). It would have been more balanced to explain to the reader – and potential judges and juries – that depending on the criteria that one uses, full false memory creation can range from 15% up to 46%. Clearly, this range provides a more reliable estimate of the potential to implant false memories for entire events than the lower bound percentage.

Third, it is remarkable that B&A did not examine false memories induced by misinformation (Loftus, 2005); a type of false memory that has also been regarded as an implanted false memory (Brainerd, Reyna, & Ceci, 2008). Of course, false memories induced by misinformation are often about small details and do not pertain to entire events. Yet, and in contrast to B&A’s central message, the general picture seems to be that these implanted false memories are articulated with high confidence. Some researchers even observed that people are more confident in these implanted false memories than in true memories (Takarangi, Parker, & Garry, 2006).

To examine whether implanted false memories induced by misinformation are, indeed, reported with high confidence, we conducted a small-scale review on misinformation studies that measured confidence (see Table 1). A search was performed on the Web of Science database using the search terms “misinformation”, “false memory”, and “confidence”. To be included in the review, studies were required to have used the misinformation paradigm and to have measured confidence in false memories. Of the 36 potential articles, nine papers (=12 studies) fulfilled our criteria. When reading the papers, an additional two papers (= three studies; total = 15 studies) were identified that met our criteria (i.e., Assefi & Garry, 2003; Loftus, Donders, Hoffman, & Schooler, 1989).

Although our review is by no means exhaustive, it does give a rough estimate of the relation between implanted false memories and confidence. Thus, in 93% (n =14) of the studies, implanted false memories were associated with confidence ratings exceeding the midpoint of the scale. A weighted percentage of the data revealed a mean confidence rating of 74% (unweighted 95% CI [0.66, 0.78]. Clearly then, confidence is often high in implanted false memories resulting from misinformation, a finding that runs counter to B&A’s idea that participants are often not very sure about their implanted false memories.

Thus, the picture is much more complex than B&A want the reader to believe on the basis of their selective review of the extant literature. Another issue is that B&A ignore courtroom realities, a point that we address in Smeets, Merckelbach, Jelicic, and Otgaar (2016). 

Table 1

Implanted False Memories Studies Elicited by the Misinformation Paradigm Measuring Confidence

Authors Participants (adults) Confidence Rating Scale
Loftus et al. (1989); Exp. 1 204 3.5 1 to 5
Loftus et al. (1989); Exp. 2 338 4.1 1 to 5
Pickel (1999) 86 5.13 1 to 10
Assefi & Garry (2003) 148 3.3 and 3.6 1 to 5
Mitchell et al. (2003) 51 1.49 and 2.20 (from Figure) 1 to 3
Takarangi et al. (2006); Exp. 1 40 4.04 1 to 5
Takarangi et al. (2006); Exp. 2 40 3.74 1 to 5
Paz-Alonso & Goodman (2008) 232 3.76 1 to 5
Foster et al. (2012); Exp. 1 64 3.81 1 to 5
Foster et al. (2012); Exp. 2 96 3.80 and 4.40 1 to 5
Van Damme & Seynaeve (2013) 300 3.49 1 to 5
Fenn et al. (2014) 107 3.61 1 to 8
Jack et al. (2014) 48 3.9 (from Figure) 1 to 5
Dodson et al. (2015); Exp. 1 59 76% and 84% 50% to 100%
Dodson et al. (2015); Exp. 2 96 75.3% and 76.3 50% to 100%




Assefi, S.L., & Garry, M. (2003). Absolut® memory distortions: Alcohol placebos influence the misinformation effect. Psychological Science, 14, 77-80.*

Brainerd, C.J., Reyna, V.F., & Ceci, S.J. (2008). Developmental reversals in false memory: A review of data and theory. Psychological Bulletin, 134, 343-382.

Brewin, C., & Andrews, B. (in press). Creating memories for false autobiographical memories in childhood: A systematic review. Applied Cognitive Psychology.

Dodson, C.S., Powers, E., & Lytell, M. (2015). Aging, confidence, and misinformation: Recalling information with the cognitive interview. Psychology and Aging, 30, 46-61.*

Fenn, K.M., Griffin, N.R., Uitvlugt, M.G., & Ravizza, S.M. (2014). The effect of Twitter exposure on false memory formation. Psychonomic Bulletin & Review, 21, 1551-1556.*

Foster, J.L., Huthwaite, T., Yesberg, J.A., Garry, M., & Loftus, E.F. (2012). Repetition, not number of sources, increases both susceptibility to misinformation and confidence in the accuracy of eyewitnesses. Acta Psychologica, 139, 320-326.*

Goff, L.M., & Roediger, H.L. (1998). Imagination inflation for action events: Repeated imaginings lead to illusory recollections. Memory & Cognition, 26, 20-33.

Jack, F., Zydervelt, S., & Zajac, R. (2014). Are co-witnesses special? Comparing the influence of co-witness and interviewer misinformation on eyewitness reports. Memory, 22, 243-255.*

Loftus, E. F. (2005). Planting misinformation in the human mind: A 30-year investigation of the malleability of memory. Learning & Memory, 12, 361–366.

Loftus, E.F., Donders, K., Hoffman, H.G., & Schooler, J.W. (1989). Creating new memories that are quickly accessed and confidently held. Memory & Cognition, 17, 607-616.*

Mitchell, K.J., Johnson, M.K., & Mather, M. (2003). Source monitoring and suggestibility to misinformation: Adult age-related differences. Applied Cognitive Psychology, 17, 107-119.*

Otgaar, H., Scoboria, A., Howe, M.L., Moldoveanu, G., & Smeets, T. (in press). Challenging memories in children and adults using an imagination inflation procedure. Psychology of Consciousness: Theory, Research, and Practice.

Paz-Alonso, P.M., & Goodman, G.S. (2008). Trauma and memory: Effects of post-event misinformation, retrieval order, and retention interval. Memory, 16, 58-75.*

Peters, M.J.V., Horselenberg, R., Jelicic, M., & Merckelbach, H. (2007). The false fame illusion in people with memories about a previous life. Consciousness and Cognition, 16, 162-169.

Pickel, K.L. (1999). Distinguishing eyewitness descriptions of perceived objects from descriptions of imagined objects. Applied Cognitive Psychology, 13, 399-413.*

Smeets, T., Telgen, S., Ost, J., Jelicic, M., & Merckelbach, H. (2009). What’s behind crashing memories? Plausibility, belief and memory in reports of having seen non-existent images. Applied Cognitive Psychology, 23, 1333-1341.

Takarangi, M.K.T., Parker, S., & Garry, M. (2006). Modernising the misinformation effect: The development of a new stimulus set. Applied Cognitive Psychology, 20, 583-590.*

Van Damme, I., & Seynaeve, L. (2013). The effect of mood on confidence in false memories. Journal of Cognitive Psychology, 25, 309-318.*

*: papers included in the review

Commentary 2: (Authors: Tom Smeets, Harald Merckelbach, Marko Jelicic, & Henry Otgaar)

Dangerously Neglecting Courtroom Realities

When looking at false memory phenomena, there are two perspectives. One could go from the lab to the court, assuming that researchers first became interested in false memories and then generalized the conclusions that could be drawn from the gathered empirical evidence to court cases in which memory accuracy of an eyewitness or victim was crucially important for justice to be served. Alternatively, one could go from the court to the lab. Evidently, many researchers in the field of false memory have taken this second route. They are familiar with cases in which innocent people were convicted based on false memories and it was this tragedy that inspired and informed their lab research (e.g., Loftus, 2002, McNally, 2012). The statistics of the Innocence Project show that in a considerable proportion of miscarriages of justice, mistaken eyewitness testimonies and false confessions play a prominent role (http://www.innocenceproject.org; e.g., Scheck, Neufeld, & Dwyer, 2001). At minimum, this suggests that the problem of false memories in courts should not be trivialized. In the U.K., a topical dissertation regarding cases brought to the Criminal Cases Review Commission (CCRC) revealed that in many of these cases, the applicant argued that a key witness (or witnesses) had been mistaken at trial (Heaton, 2013).

Many memory researchers have been inspired by legal cases featuring erroneous memory – ranging from minor (albeit non-trivial) memory distortions to full-blown false memories – to examine potential causes of false memories in eyewitnesses, victims, and defendants. These memory researchers never aspired to provide the courts with precise risk taxations but rather aimed to inform the legal arena of why and when memory errors tend to occur. To be sure, one of the problems in generalizing from the lab to the court has to do with limited research relying on clinical samples. Indeed, research on how false memories may be elicited in the laboratory by and large employed non-clinical samples of clever undergraduate students whose memory, verbal skills, and motivation may not at all be representative of individuals who end up in a court case as witnesses, victims or defendants. Consider the prototypical person taking legal actions based on recovering memories of childhood sexual abuse. Such a person is routinely in search of an explanation for current complaints such as a depression, anxiety, or an eating disorder, and it is this very need for an explanation that may render this person vulnerable to accepting seemingly plausible reasons such as childhood sexual abuse (i.e., “motivated cognition”; see Loftus & Davis, 2006; Merckelbach, 2003). It was not until studies regarding genuine and false memories in undergraduate samples had provided clues about potential causes underlying recovered memories that research started focusing on people actually reporting memories of childhood sexual abuse (McNally, 2012).

B&A’s practical message seems to be that expert witnesses should be wary when informing the legal arena about the scale on which full false memories might be induced. We would argue that this message is naïve: even if one accepts 15% as an accurate higher bound estimate of the false memory base rate induced by mildly suggestive techniques in intelligent undergraduates, this percentage is alarmingly high. B&A stress that most paradigms elicit false beliefs rather than memories and that, hence, the base rate of full false memories is lower than previously assumed. However, even if techniques such as the false feedback paradigm are more likely to elicit false beliefs than false memories, this is still perilous for legal settings. Evidence is accumulating that behavioural consequences are driven by beliefs and less by recollections (Bernstein, Scoboria, & Arnold, 2015). This suggests that a false belief of child sexual abuse might be sufficient to start a legal proceeding.

One other issue that should be considered is that expert witnesses may not be very good in determining whether a childhood memory that forms the basis for an allegation is false or accurate. After all, in terms of accompanying emotions and bodily signs false memories might appear as genuine as true memories (e.g., McNally, Lasko, Clancy, Macklin, Pitman, & Orr, 2004). Thus, all that expert witnesses can do is point at the base rates of false memories in lab studies that used mild interventions and then compare these to the interventions that might have contributed to the memory of the event that is the focus of the court case. And while there is an extensive literature on false memories in the lab – as the review by B&A nicely demonstrates –, studies on the false memory potential of routine clinical interventions are conspicuously absent. What happens if – as is done in Eye Movement Desensitization and Reprocessing (EMDR) – patients are encouraged to retrieve memories by providing them with the metaphor of memory as a perfectly recorded movie? What happens if – as is done in schema-focused therapy – patients learn that their sense of who they are (their “self”) consists of early maladaptive schema’s containing buried childhood memories? What happens when patients’ aversive memories undergo positive reinstatements? We do not know, simply because there is almost no scientific literature addressing these issues. Brewin (2015, p.21) recently advanced the idea that “psychotherapy creates new memories.” If true, legitimate follow-up questions would be whether and on what scale interventions create new memories that are false. What we do know is that therapeutic interventions sometimes harm people (Crawford, Thana, Farquharson, Palmer, Hancock, Bassett, Clarke, & Parry, 2016; Lilienfeld, 2007) and that unlike pharmacological trials, psychotherapeutic trials seldomly record adverse side effects (Parry, Crawford, & Duggan, 2016). It is this absence of vital information that should be noted as an important limitation in court reports. Indeed, future studies in this field focusing on the false memory potential of routine clinical interventions in symptomatic individuals are urgently needed.

In sum, we argue that B&A’s review is selective in the studies and in the topics it addressed and in doing so, sketches a picture that could lead researchers to incorrectly assume that outside the psychological lab, false memories have a low probability. That would be unfortunate, if only because it would neglect the realities of the courtroom in which false memories may wreak havoc in the lives of innocent people.



Bernstein, D.M., Scoboria, A., & Arnold, R. (2015). The consequences of suggesting false childhood food events. Acta Psychologica, 156, 1-7.

Brewin, C.R. (2015). Reconsolidation versus retrieval competition: Rival hypotheses to explain memory change in psychotherapy. Behavioral and Brain Sciences, 38, e4.

Brewin, C., & Andrews, B. (in press). Creating memories for false autobiographical memories in childhood: A systematic review. Applied Cognitive Psychology.

Crawford, M.J., Thana, L., Farquharson, L., Palmer, L., Hancock, E., Bassett, P., Clarke, J., & Parry, G.D. (2016). Patient experience of negative effects of psychological treatment: Results of a national survey. British Journal of Psychiatry, 208, 260-265.

Heaton, S.J. (2013). A critical evaluation of the utility of using innocence as a criterion in the post conviction process. Doctoral thesis, University of East Anglia.

Lilienfeld, S.O. (2007). Psychological treatments that cause harm. Perspectives on Psychological Science, 2, 53-70.

Loftus, E. F. (2002). Memory faults and fixes. Issues in Science and Technology, 18, 41.

Loftus, E.F. & Davis, D. (2006). Recovered memories. Annual Review of Clinical Psychology, 2, 469-498.

Merckelbach, H. (2003). Taking recovered memories to court. In P. J. van Koppen (Ed.), Adversarial versus inquisitorial justice: Psychological perspectives on criminal justice systems. Perspectives in law & psychology, Vol. 17 (pp. 119-130). New York: Kluwer Academic/Plenum Publishers.

McNally, R.J. (2012). Searching for repressed memory. In R. F. Belli (Ed.), True and false recovered memories: Toward a reconciliation of the debate (pp. 121-147). Vol. 58: Nebraska Symposium on Motivation. New York: Springer.

McNally, R.J., Lasko, N.B., Clancy, S.A., Macklin, M.L., Pitman, R.K., & Orr, S.P. (2004). Psychophysiological responding during script-driven imagery in people reporting abduction by space aliens. Psychological Science, 15, 493-497.

Parry, G.D., Crawford, M.J., & Duggan, C. (2016). Iatrogenic harm from psychological therapies – Time to move on. British Journal of Psychiatry, 208, 210-212.

Scheck, B., Neufeld, P., & Dwyer, J. (2001). Actual innocence: When justice goes wrong and how to make it right. New York: Signet Books.

Note: The published commentaries will also include abstracts and might slightly differ from the current versions.


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The fall of ego depletion?

Is there another crisis in psychology? If you have not heard it, a huge replication attempt on ego depletion has recently been conducted. This hypothetical state of reduced self-control has received immense empirical attention in the past decades. I have written about this replication study before and yes, we participated too. The results have just been put online and will soon be published in Perspectives on Psychological Science. In short: No convincing evidence for ego depletion was found. Nothing. Nada.

What now? The original ego depletion researchers, Roy Baumeister and Kathleen Vohs, wrote a commentary on the failed replication. Their comment in a nutshell: 1) the replication studies did not measure ego depletion, 2) there is an abundance of previous studies showing that ego depletion exists which cannot be “dismissed”. What to make of this commentary?

First of all, it is relevant to understand how such a replication study works. Martin Hagger and Nikos Chatzisarantis were the ones who proposed to conduct such a replication study. They contacted Baumeister and Vohs to agree on the task that should be used for a replication attempt. Baumeister and Vohs now stated that it was a mistake that they said “yes” to the task used. They say that although previous work has shown that this task leads to ego depletion, the task has not been frequently used in the literature and actually does not tap into ego depletion. I find this argument not really persuasive.

Why? Well, a recent meta-analysis by Evan Carter and colleagues showed that even when looking at other and more ways to induce ego depletion, still no convincing evidence exists for the effect. Ok, Baumeister and Vohs were brave enough to say that they made a mistake, but I wonder what would have happened when the replication attempt would have generated evidence for the ego depletion effect. Would they then also say the task did not measure ego depletion? I do not think so. The commentary showed that they believe so strong in ego depletion that they even argued that one just cannot dismiss all the positive findings on ego depletion.

In my view, their belief comes close to belief perseverance and confirmation bias in which negative evidence is discounted and only confirming evidence is searched for. I say this because in Carter’s meta-analysis, the point was made that the ego depletion literature suffers from publication bias. Although Carter and colleagues stated that this publication bias might perhaps not have hugely affected their meta-analytic finding, the bias exists. From my own experience, I concur. In our labs, my colleagues and I have had the same experience in which on many occasions, ‘standard’ procedures to elicit ego depletion did not evoke any reduced self-control. I guess many other labs have had the same experience.

What to do now? Baumeister and Vohs proposed to organize a preregistered multisite replication using many well-tested procedures. I applaud this initiative. By the way: there is already a preregistered study on ego depletion using a well tested procedure that has recently been published. Do you know what they found? Nothing. Nada.



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Where were you on Monday between 2 and 4 pm? With alibis the devil is in the detail.

In 1984, Jennifer Thompson was raped in her student flat by a stranger. Five days later, Ronald Cotton was questioned about his alibi. He explained that he was together with friends at the time of the crime. But shortly after, he changed his statement: He had slept on the couch in his mother’s house mother at the implied time. Is this statement to be trusted? Did Cotton lie initially?

The latter is what 80 percent of investigators assume, according to research conducted in the US: If suspects change their alibi later on, the most probable cause is that they lied before. To test this assumption, two American researchers asked 255 students to provide an alibi statement for four time periods in the past. Most participants, namely 88 percent, remembered the specified periods and provided a statement about their whereabouts. In the second part of the study it became trickier: participants had to provide evidence in support of their statement. In a second testing session, about one third of the participants indicated that they had been mistaken during the first session and that they had to correct their alibi. A follow-up study showed that most alibi statements contained inconsistencies. These inconsistencies were found for all aspects of the statement: the persons involved, locations, time and chronology of events. The authors conclude that inconsistencies in alibis are a natural side product of our imperfect memory that occur in suspects, much as they do in eyewitnesses.

But how did it end for Ronald Cotton? After his first statement, he realized that he had confused two weekends and therefore had to correct his alibi. In 1985, he was convicted to life in prison (partly) because his alibi was not believed. Today, we know that he was innocent, thanks to DNA evidence. He was released from prison in 1995.

Dysart, J. E., & Strange, D. (2012). Beliefs about alibis and alibi investigations: A survey of
law enforcement. Psychology, Crime & Law, 18, 11-25.
Olson, E. A., & Charman, S. D. (2012). ‘But can you prove it?’ – examining the quality of
innocent suspects’ alibis. Psychology, Crime & Law, 18, 453-471.
Strange, D., Dysart, J., & Loftus, E. F. (2014). Why errors in alibis are not necessarily
evidence of guilt. Zeitschrift für Psychologie, 222, 82-89.

Written by Melanie Sauerland, this blog was originally published in German at de.in-mind.org

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I am innocent and I will prove it later. No, a confession trumps all the other evidence.

If a confession is obtained, the investigation is commonly completed, followed by the trial and oftentimes the conviction of the suspect. A confession is considered the queen of evidence. But what happens when an innocent person confesses to a crime that she or he did not commit? This happens more often than one would think. But shouldn’t we then find proof of innocence? When looking at proven cases of innocent convictions, the absence of exculpatory evidence is striking. How can this be?

Let us consider the case of a woman who was raped and killed in Pennsylvania in August 1987. The police investigation focused on Barry Laughman who confessed to the murder after the police misinformed him that they had found his fingerprints at the crime scene. The blood testing showed that the perpetrator as well as the victim had type A blood. However, Laughman had type B blood. This information should have excluded him as the perpetrator. At trial, however, an alleged expert who knew about the confession introduced speculative, unfounded theories that “explained” the change in blood type. And so Laughman was convicted to life in prison.

This case demonstrates how a confession can influence the evaluation of other evidence. Such information not only has the potential to affect fingerprint evaluations, but also blood tests and even DNA analyses, as research has shown. How is that possible? Contrary to general believes, the evaluation of physical evidence comprises subjective components. Fingerprints found at the crime scene are often incomplete and DNA samples of poor quality. If this is the case, room for interpretation unfolds and the available context information (e.g., a confession) can exert its influence on the evaluation of evidence, for example when an expert is to decide whether two fingerprints are sufficiently similar. It is in these ambiguous situations that primarily cues supporting the prior hypothesis are considered (forensic confirmation bias).

Laughman was exonerated based on DNA analyses after 16 years in prison. The results of this analysis were believed, despite the confession.

Keywords: False confessions, miscarriage of justice, forensic confirmation bias


Kassin, S. M., Bogart, D. & Kerner, J. (2012). Confessions that corrupt evidence from theDNA exoneration case files. Psychological Science, 23, 41-45. doi:10.1177/0956797611422918

Kassin, S. M., Dror, I. E. & Kukucka, J. (2013). The forensic confirmation bias: Problems,perspectives, and proposed solutions. Journal of Applied Research in Memory and Cognition, 2, 42-52. doi:10.1016/j.jarmac.2013.01.001

Written by Teresa Schneider and Melanie Sauerland, this blog was originally published in German at de.in-mind.org.


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Mediation lost de vechtscheiding niet op

Opiniebijdrage in Trouw, 6 februari 2016

Mediation wordt gepropageerd als hét middel bij conflictscheidingen. Ten onrechte, beweren Corine de Ruiter en Ferko Öry. De feiten onderzoeken is veel belangrijker.

Het kabinet is sinds een paar jaar zeer actief om de situatie van kinderen bij een vechtscheiding te verbeteren. Een terugkerend thema is mediation. Er ligt zelfs een wetsvoorstel voor verplichte mediation bij echtscheidingen, dat door een aantal politieke partijen wordt gesteund. Maar mediation werkt bij de meeste vechtscheidingen niet en kan gevaarlijk zijn. Er bestaat een aantal hardnekkige mythen over conflictscheidingen. Die mythen domineren het debat en belemmeren effectieve oplossingen voor dit complexe probleem. Ten eerste is er de mythe dat omgang met beide ouders altijd het beste is voor elk kind. Op basis van deze mythe is de echtscheidingswetgeving de afgelopen jaren gewijzigd. In 2009 werd het verplichte ouderschapsplan ingevoerd, waardoor ouders pas mogen scheiden als er een gezamenlijk opgesteld ouderschapsplan is overeengekomen. De invoering van dit ouderschapsplan heeft echter niet geleid tot minder vechtscheidingen, integendeel, stelt de jurist Marit Tomassen-van der Lans in haar proefschrift in 2015.


Een tweede mythe is het idee dat mediation helpt in het voorkomen van vechtscheidingen. Mediation wordt zelfs gepromoot als dé oplossing voor conflictscheidingen. Niets is minder waar. Het WODC concludeerde in 2015 dat “het voorbarig is om conclusies te trekken ten aanzien van effectiviteit van mediation en scheidingseducatie in het voorkomen van vechtscheidingen met het oog op het verbeteren van het welzijn van het kind en dat de bevindingen van de onderzochte studies niet bemoedigend zijn”. Uit recent onderzoek uit Noorwegen, waar sinds 1991 verplichte mediation bij wet is ingevoerd, blijkt dat bij 63 procent van de conflict-scheidingsparen de mediation vroegtijdig stopte zonder dat het tot concrete afspraken kwam, tegenover 12 procent van de ‘normale’ paren.

Feiten achterhalen

Een conflictscheiding is een ingewikkeld probleem waarbij sprake kan zijn van narcistische en borderline-persoonlijkheidsstoornissen bij één of beide ex-partners, een voorgeschiedenis van ernstig relationeel geweld, beschuldigingen en vermoedens van kindermishandeling, en ouders die het kind proberen te vervreemden van de andere ouder door kwaadsprekerij. Voorafgaand aan enige vorm van hulp dienen de feiten achterhaald te worden, ook wel ‘waarheidsvinding’ genoemd. Dat dit vaak een reconstructie achteraf is, op basis van meerdere en verschillende informatiebronnen, doet daar niet aan af. Feitenonderzoek betekent onderzoek naar de voorgeschiedenis van geweld in de partnerrelatie, met een gestructureerde interviewmethode. De twee voormalige echtelieden worden ieder apart gesproken en wanneer er grote discrepanties bestaan tussen de verhalen van beiden, dienen ook andere informatiebronnen geraadpleegd te worden, zoals politiegegevens, medische dossiers, en gesprekken met personen uit het sociale netwerk. Op deze wijze ontstaat inzicht in de aard van de machtsverhouding tussen de ex-partners, welke vormen van geweld er gespeeld hebben of nog spelen, of er sprake is van psychische of verslavingsproblemen. Zonder gedegen feitenonderzoek naar geweld in de partnerrelatie door forensisch geschoolde professionals, kunnen de belangen van het kind in een conflictscheiding niet gewaarborgd worden. Ook als er door een van de ex-partners beschuldigingen geuit worden over kindermishandeling door de andere partner, zullen die feitelijk onderzocht moeten worden. Dat stelde overigens ook de Kinderombudsman al in het rapport ‘Is de zorg gegrond?’ uit december 2013. Ook de Inspectie voor de Gezondheidszorg uit in haar Jaarbericht over 2014 grote zorgen over het tekort aan waarheidsvinding binnen de jeugdzorg, inclusief de Raad voor de Kinderbescherming. Het is de hoogste tijd dat feiten in plaats van mythen leidend worden in de aanpak van conflictscheidingen in Nederland.

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Ken je zaak (niet)

Er bestaat die tegeltjeswijsheid dat wie slechts de helft van een zaak kent, eigenlijk niets weet. Maar klopt dat wel? Is het wellicht beter om helemaal niets te weten van een zaak? Een voorbeeld. Bruce wilt wat geld storten bij de plaatselijke bank. Eenmaal binnen ziet hij een man met een bivakmuts de bank binnenstormen. Zwaaiend met een geweer schreeuwt hij dat iedereen op de grond moet liggen. De overvaller slaagt erin een flinke buit mee te nemen. Een aantal dagen later vraagt de politie aan Bruce of hij mee wilt komen naar het politiebureau. Om hem wat vragen te stellen over de overval. Rechercheur Robert heeft de zaak goed voorbereid. Hij heeft de stukken van de zaak goed doorgelezen. Een gedegen voorbereiding is namelijk aan te bevelen voor het getuigenverhoor. Denkt Robert.

Interviews met getuigen worden doorgaans goed voorbereid. De politieagent die een interview afneemt, heeft zich doorgaans goed ingelezen in de zaak. Om zo goede vragen te kunnen stellen. Niets mis mee met zo’n voorbereiding, zou je zeggen. Maar kan achtergrondkennis ook nadelig zijn? Volgens recent onderzoek wel. Zo lieten de Amerikaanse psychologen Murrie en collega’s zien dat het voor forensisch psychologen uitmaakt of ze kennis hebben voor wie ze werken: een advocaat of officier van justitie. De onderzoekers lieten forensisch psychologen zaakdossiers lezen over seksueel delinquenten. Wanneer forensisch psychologen het idee hadden dat ze voor een advocaat werkten, gaven ze lagere recidivescores dan wanneer ze dachten dat ze voor een officier van justitie werkten. Een allegiance bias noemden de onderzoekers dat.

Dat biases de oordeelsvorming vertroebelen, weten we allang. Zo wordt bij de politie gewaarschuwd voor tunnelvisie of de confirmation bias: dat je alleen op zoek gaat naar bewijs dat jouw hypothese bevestigt en bewijs negeert dat jouw hypothese verwerpt. Vandaar dat een line-up of Oslo-confrontatie dubbelblind dient te worden uitgevoerd. De politieagent die een line-up uitvoert, weet bijvoorbeeld niet wie de verdachte is in een line-up. Zo voorkom je dat een politieagent onbewust aan een getuige laat weten wie de verdachte is. Waardoor de kans op onjuiste identificaties kleiner wordt. Maar hoe zit het dan bij getuigenverhoren?

Ook daar schijnt achtergrondkennis over een zaak hinderlijk te zijn. In een pas geaccepteerd artikel van de Amerikaanse psychologen Rivard en collega’s werd aangetoond dat “blinde” interviewers het beter doen dan interviewers met zaakkennis. Interviewers die niets afwisten van een zaak lokte meer correcte informatie uit dan interviewers die zich wel hadden voorbereid. Ook stelde interviewers die zich hadden voorbereid vaker een suggestieve vraag aan het begin van een verhoor dan blinde interviewers. Achtergrondkennis over een zaak kan dus interviewers beperken in het stellen van vragen. Wat is de verklaring hiervoor? Heeft allemaal te maken met verwachtingseffecten. Interviewers met zaakkennis hebben verwachtingen over de zaak en die verwachtingen vertroebelen de manier van interviewen.

En Robert? Die had Bruce toch beter geïnterviewd zonder enige voorbereiding. Had hij betere vragen gesteld. En juiste verklaringen gekregen. Zou hem ook meer tijd hebben gegeven om andere zaken te doen. Zoals boeven vangen.

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Have you become a witness? Do it yourself and conduct your own interview

Shortly after the crime, investigators discover fingerprints and trails of blood at the crime scene that could stem from the perpetrator. Yet, two weeks pass until experts finally collect these traces. Who would expect them to still find anything of use? What seems really strange, even unthinkable, when it comes to handling physical evidence, is business as usual when the police deal with eyewitness evidence. In this blog we will present a remedy for this, a new method ensuring immediate recording of eyewitness accounts.

Due to limited police resources, witnesses are often interviewed with a delay of days or weeks after the crime occurred. In this case, witnesses can be expected to roughly recall the incident, while specific details, such as the license plate number, are likely to be forgotten at this stage. However, specific details are often most relevant for solving a case. Forgotten information is lost to the investigators just as fingerprints that were wiped away before they are collected. Hence, witnesses’ recollections should be treated just as physical evidence – they should be secured, that is, recorded in an interview, immediately after the crime.

But what if this is not possible due to limited police resources? In this case witnesses can interview themselves with the Self-Administered Interview (SAI; Dutch: Zelfrapportage voor Getuigen, ZeG). This booklet is distributed to witnesses at the crime scene where they complete it in writing, literally interviewing themselves. The SAI contains several recall-enhancing instructions, including mentally reinstating the incident before writing down the recollections. The tool is suitable for all types of crime. It consists of several sections in which the incident, the perpetrator(s), potential vehicles, further witnesses, and the witnessing conditions can be described. Moreover, witnesses are asked to draw a sketch of the scene. The evaluation of the SAI is positive: Immediately after the crime, it elicits comprehensive and accurate statements that can be used for investigation purposes. Furthermore, research has shown that witnesses who first completed an SAI perform better in a subsequent interview. That is, the SAI preserves the witness’ memory for a later interview. As such, it supports the police during the investigations. The tool is already in use in a few countries, among them the UK, Norway and the Netherlands.


Hope, L., Gabbert, F., & Fisher, R. P. (2011). From laboratory to the street: Capturing witness memory using the Self-Administered Interview. Legal and Criminological Psychology, 16, 211-226. doi:10.1111/j.2044-8333.2011.02015.x

Krix, A. C., Sauerland, M., & Schreuder, M. J. (2013). Hoe getuigen zichzelf kunnen verhoren: de Zelfrapportage voor getuigen. Expertise en Recht, 5/6/2013, 180-184.


Written by Alana C. Krix and Melanie Sauerland, this blog was originally published in German at de.in-mind.org.

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Children as witnesses – Can we believe them?

Children are less reliable eyewitnesses than adults. This is because their memories are less accurate and because they are more susceptible to suggestion. This opinion is widespread and has been endorsed in court cases. But is this always true? Or can children sometimes even be better witnesses than adults?

The Whisper von Brian Smithson via flickr

The Whisper von Brian Smithson via flickr

Two trials about repeated child sexual abuse that attracted intense media coverage took place during the late 1990s in Germany: the Montessori-trials and the Worms trials. Child testimonies were the only pieces of evidence in both trials. However, induced by suggestive pressure, these testimonies were erroneous: The well-meaning adults, who interviewed the children about their allegations, were so convinced about the occurrence of the abuse that they primarily aimed at finding supportive evidence for this idea during the interviews. To this end, they resorted to suggestive interviewing techniques: They repeated their questions and provided misleading cues until the children finally made the expected allegations. Numerous experiments confirmed the negative influence of erroneous information and suggestive questions on memory, especially in children. It is, for example, easier to convince younger children compared to older children about being abducted by a UFO by means of a fictitious newspaper article. But do these findings imply that one should generally not believe children and that children are bad witnesses?

No! If children disclose spontaneously and in their own words and if open questions (e.g., “Do you know why you are here?”, “Tell me more about that”) are used, child testimonies can be highly reliable. Recent memory experiments even show that children sometimes outperform adults. That is because adults tend to fill memory gaps with experience-based knowledge. Children, on the other hand, do not possess that much so-called script knowledge.

Scepticism towards child testimony is therefore warranted if it is likely that the child witness was exposed to suggestions. To assess the validity of a testimony it is thus necessary to thoroughly analyse the initial formation and development over time of the testimony (Was the child exposed to erroneous information?) and the circumstances of questioning (Were suggestive, misleading questions posed?). Children, just like adults, are not always reliable witnesses, but they certainly can be.


Brackmann, N., Otgaar, H., Sauerland, M., & Merckelbach, H. (2015). Children are poor witnesses. Or are they? In Mind, 24, 1-6. (see http://www.in-mind.org/article/children-are-poor-witnesses-or-are-they)

Brainerd, C. J., Reyna, V. F., & Ceci, S. J. (2008). Developmental reversals in false memory: A review of data and theory. Psychological Bulletin, 134, 343-382. doi:10.1037/0033-2909.134.3.343

Written by Nathalie Brackmann, Alana C. Krix, and Melanie Sauerland. This blog was originally published in German at de.in-mind.org.

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Twee tips voor Delta Lloyd

Onlangs maakte verzekeraar Delta Lloyd bekend een proef te starten met stemanalyse-software. Met deze software zouden medewerkers een objectieve inschatting kunnen maken over het waarheidsgehalte van een claim. En zo zouden ze verzekeringsfraude tegen kunnen gaan. Of je telefoon wel echt gestolen is dus.

De verzekeraar hecht er aan om heel transparant te zijn over de inzet van de software: “Verzwijgen vinden we niet integer”. De klant zal dan ook voorafgaand aan een gesprek geïnformeerd worden dat er getest gaat worden. Zo’n mededeling zou er dan ongeveer als volgt uit moeten zien: “Dit gesprek wordt geanalyseerd met behulp van software die op geen enkele wijze kan aantonen of u de waarheid spreekt”.

Want daar komt het namelijk op neer. Neem het recente Amerikaanse onderzoek van Frank Horvath en collega’s. Zij paste de software toe op politieverhoren van 74 verdachten. Achttien van deze verdachten legden later een bekentenis af, waarmee hun eerdere leugenachtigheid redelijkerwijs kwam vast te staan. In deze groep wees de software 52 % als hele eerlijke mensen aan. Je kunt dus net zo goed een muntje opgooien.

Of neem het onderzoek uitgevoerd in opdracht van het Amerikaanse Ministerie van Justitie. Meer dan 300 arrestanten werden ondervraagd over hun recente drugsgebruik. Deze ondervragingen werden geanalyseerd met behulp van de software, en de uitslag werd naast de uitslag van een urinetest gelegd om de nauwkeurigheid vast te stellen. Ook hier leverde de software een nauwkeurigheid op vergelijkbaar met de kwaliteit van kop-of-munt-beslissingen.

Toch hoopt Delta Lloyd dat het aantal frauduleuze claims vanwege de proef met 5% afneemt. Maar hoe gaan ze dat dan eigenlijk vaststellen? Om zo’n getal in kaart te brengen, moet je immers weten hoeveel frauduleuze claims er nu zijn, en hoeveel er na afloop van de proef zijn. Maar als Delta Loyd nu al weet hoeveel valse claims er zijn, kunnen ze die beter meteen afwijzen. Gratis tip. Graag gedaan.

Ondertussen doet de afdeling Integriteitszaken van Delta Lloyd zaken met een bedrijf dat tot twee maal toe op de vingers is getikt voor misleiding en oneerlijkheid. Dat is dan wel weer geinig. Daarom nog een tweede tip voor Delta Lloyd: zo vraag je je geld terug. Wederom graag gedaan.

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