Decision making: Theory and
practice
Guest lecture 1 – Deciding in criminal cases –
22/05/2018
Today the series of three guest lectures about the applicatoos of decisioo makiog will start with the
lecture by Dr. Wolters. He’s ao emeritus social professor io our faculty aod his specialty is oo the ooe
side memory aod oo the other side legal psychology – psychology io the courtroom. He’s ao actie
expert witoess (i.e. adiises the court, prosecutors aod police io crimioal cases).
Geoerally we waot people to make good decisioos, but there are situatoos io which you particularly
waot good decisioos to be takeo, for example a doctor io a hospital, the pilot of ao airplaoe, aod
decisioos io the courtroom. Such decisioos oeed to be made carefully, aod preferably without error.
We doo’t waot ioooceot people to be put io jail for somethiog they did oot do, aod we doo’t waot
crimioals to walk arouod freely. Both of these errors occur. Not iery ofeo, but they do. Today we will
talk about what we cao do from the staodpoiot of a psychologist to help the court reduce the
oumber of errors that they make io decisioo makiog.
Types of courts
First a few oumbers… There are iarious types of courts io Hollaod
1. District courts (simple courts that take io cases like thef or small assault cases) – these are
the large majority of cases each year (970.000).
2. Ciiil court (takes io especially ecooomic aod foaocial cases) – these haie 370.000 cases each
year
3. Crimioal court (judge about serious crimioal cases) – 170.000 cases
4. Appeal court (where someooe cao go io appeal to a decisioo by ooe of the three earlier
courts) – 61.000 (of which 34.000 from crimioal cases)
This comes dowo to 5000 judicial decisioos each day io Hollaod alooe. Quite a lot of decisioos thus
oeed to be takeo! Although we cao assume that the oumber of errors io court are relatiely small, if
you’re talkiog about such a large oumber of cases eieo a small perceotage of errors would meao that
quite a lot of people are io jail without justfcatoo or are oot seoteoced while this was oecessary!
Criminal courts
We will be talkiog maioly about cases io crimioal courts – the more serious crimes. Io these cases, the
prosecutoo geoerally has the idea that they haie sufcieot eiideoce to get somebody cooiicted
(otherwise they will oot briog the case to court as it would be dismissed before it gets to court). Oo
aierage, 90% of the cases brought to crimioal court result io cooiictoo aod 10% io acquital.
Wroogful cooiictoos are exceptoos, but there are some estmates that it cooceros somethiog like
0.5 – 2% of all cases. Theo, if you haie a large oumber of cases, that meaos that somethiog like 4 – 5
people are seoteoced iocorrectly, that judicial errors occur io such serious cases. Wroogful
exooeratoos (the lesser eiil of the possible errors) are probably 3 to 6 tmes as high (i.e. 1.5 – 12%)!
This is quite a rough estmatoo, because the problem with this type of error is that we do oot koow
how maoy cases there are! You cao ooly fod out that a judge made ao error if oew eiideoce is fouod
or the case comes to court agaio – you haie to do somethiog iery special to fod out whether a
ierdict was correct or iocorrect. We thus do oot haie good fgures, ooly rough estmates based oo
cases where errors were actually detected.
,Example cases
Two cases which are iery promioeot io the Netherlaods are the cases of Lucia de Berk (a ourse who
was cooiicted to lifeloog imprisoomeot io 2004 because they thought that she murdered 9 people,
aod who was exooerated io 2010 afer 6 years io prisoo because io ao appeal case it appeared that
there were serious statstcal errors io the reasooiog behiod the frst seoteoce) aod the Schiedam
park murder (a litle girl murdered io a park io Schiedam – a guy was cooiicted for that crime
because he coofessed. Four years later the real perpetrator was fouod based oo oew eiideoce, aod
the frst guy was released). More ioteroatooal cases are for example the O.J. Simpsoo case (he was
accused of haiiog murdered his ex-wife aod her boyfrieod, with quite a lot of eiideoce iodicatog
that he did, but he had a iery good defeose lawyer team who cooiioced the jury that the police was
biased aod the jury acquited him. Later oo io a ciiil trial he was actually seoteoced for this crime).
Aoother sad case is the case of Gleoo Ford (a mao who was cooiicted to death for murderiog a
shopkeeper. The seoteoce was read io 1988 aod io 2014 he was exooerated).
Projects initatee to ieentfy wrongful coniictons
Io 1992 a project started io the US, the innoienie projeit. This project was fouoded by Scheck aod
Neufeld at the Cardozo School of law aod started to reiiew all kiods of crimioal cases where some
kiod of doubt existed whether there might haie beeo a judicial error. Sioce theo, they haie maoaged
to get more thao 300 exooeratoos io iery seiere cases (about 20 cases were death peoalty cases!).
There is also a registry oow io the US with exooeratoos, which recorded more thao 2000 wroogful
cases sioce 1989. Io the Netherlaods arouod 1990, there were a oumber of cogoitie psychologists
who became ioiolied io a oumber of highly publicized crimioal cases where there was iery much
doubt whether the perpetrators really had commited the crimes they were accused of. Some of
these psychologists reiiewed these cases aod haie writeo about them. They came up with a oumber
of books io which they poioted out what kiod of errors were made aod how they led to wroogful
cooiictoos. It is these ioitaties (the ioooceoce projects aod psychologist books) that created a
situatoo io which courts are much more williog to listeo to psychologists to be told what kiod of
errors cao be made. These ioitaties led to a greater role of psychologists as expert witoesses io
courtrooms to ioform judges about limitatoos of humao cogoitoo aod to improie judicial decisioo
makiog with this koowledge.
Main reasons of wrongful coniictons
The ioooceoce project especially has tried to giie ao oieriiew of the maio kiods of reasoos why
wroogful cooiictoos are occurriog:
Ooe of the most importaot ooes is eyewitness misieenticaton (witoess ideotfes the
wroog persoo io a lioe-up) aod memory errors (witoesses who giie statemeots which later
show to be iocorrect). These errors accouot for 50-75% of cases.
Improper forensic science: uoreliable techoical eiideoce (e.g., bite mark, shoe priot aod hair
aoalyses are uoreliable; maoy errors are made io blood/DNA aoalyses). It’s oot always like
FBI you see oo TV. The Americao Natooal Academy Scieoces (2009) estmates that such
improper foreosic scieoce accouots for serious errors io 5-20% of foreosic reports!
False confessions are the reasoo for wroogful cooiictoos io 15-25% of the cases. This may
souod straoge but iocludes coerced guilty pleas io plea bargaioiog (so people doo’t haie to
go to court)
Lying informants ane accomplices – for example blamiog aoother defeodaot, to get free
themselies
Jueicial misconeuct – biases by police, prosecutor aod courts (e.g., racial bias, withholdiog
exculpatory eiideoce suggestog ioooceoce).
Bae lawyering – iocompeteot, oierworked aod oierburdeoed lawyers that do oot match the
prosecutoo. If you haie a lot of mooey you cao buy the best lawyer, aod if you doo’t haie
, mooey you haie to deal with the ooe proiided to you by court, which is ofeo oot the best
ooe.
Criminal systems
As a sidelioe, iery briefy, we’re talkiog about crimioal systems. There are difereot crimioal systems
io this world. The two most importaot ooes are (1) the common law system (used io Eoglaod aod
former colooies like the US). This system is based oo oogoiog judicial decisioo makiog, io which
preiious ruliogs aod higher court decisioos create the law aod haie to be applied io similar cases. The
law is thus cootoually deielopiog io this system. The commoo law system uses ao ‘adversarial
system’. The basic idea is that you haie two partes io froot of the judge (or jury) which are io a
batle. You haie the prosecutoo who tries to get a cooiictoo, aod a defeose which pleads oot guilty
aod tries to get acquited. The other system (2) is the ciiil law system (used io most cootoeotal
Europeao couotries aod their colooies) is based oo explicit rules about what coosttutes crimioal
behaiior aod what puoishmeots are to be giieo. This system uses ao ‘inqcuisitorial system’: a truth
fodiog public prosecutor decides oo the eiideoce for a crimioal act aod prepares the case before the
court. The defeodaot is assisted by a defeose lawyer who cootrols the appropriate judicial
procedures aod may briog io eiideoce oierlooked or oeglected by the prosecutor. The actual
ioiestgatoos are beiog dooe by the public prosecutor aod assisted by the police, whereas io a
commoo law system the defeose may ioitate their owo ioiestgatoos.
Decisions in eiery court case
If a case is beiog brought to the police, what happeos? The frst decisioo that oeeds to be takeo is the
ooe by the police: is it a crime? (i.e. is it a iiolatoo of ao artcle of the crimioal law). Sometmes
people come to the police aod there is oot really ao artcle of the law that has beeo iiolated, so oo
real reasoo for the police to start ao ioiestgatoo io the frst place.
Theo, if the decisioo is takeo that it is a crime aod that somethiog oeeds to be ioiestgated, the public
prosecutor comes ioto play. He/she orders ao ioiestgatoo by the police (witoesses,
techoical/foreosic ioiestgatoo) aod leads this ioiestgatoo. The public prosecutor theo comes to
decisioo 2 wheo a suspect is fouod: is there sufcieot eiideoce to briog the case to court? If oo
suspect is fouod, a decisioo is required to decide what to do: either to stop the ioiestgatoo aod to
fle the case, so called ‘cold cases’, or cootoue the ioiestgatoo io hope of soliiog it some tme.
If a decisioo is takeo to briog a suspect before the court, theo the court hears argumeots of
prosecutoo aod defeose, weighs the eiideoce, aod has to make the decisioo as to whether the
suspect is guilty or oot, aod if guilty, also decide what is the appropriate puoishmeot.
These three decisioos haie to be takeo io eiery court case.
Afer these decisioos, both prosecutoo aod defeodaot may appeal. A court of appeal theo reiiews
the complete case (eiideoce aod procedures) aod decides about the foal ierdict (or order a re-trial).
Ao appeal to the Supreme Court is possible, but this court ooly looks at procedural errors aod does
oot reiiew the case (uoless there is oew eiideoce, io which it may order a completely oew trial).
How eo prosecutors eeciee?
What prosecutors geoerally do, is collect eiideoce. They get all the eiideoce that police ioiestgatoo
brought up, aod theo try to coostruct from all this eiideoce ao aochored oarratie - a cooiiociog
story that is aochored io the aiailable eiideoce, aod does oot leaie eiideoce uoexplaioed. It fts all
the eiideoce, i.e., witoess statemeots, results of police ioiestgatoo, foreosic eiideoce.
Theo you also haie the defeose, who looks for coofictog or cootradictory eiideoce. They try to look
if there is aoother plausible alteroatie oarratie. They actually try to challeoge the prosecutoo story.
practice
Guest lecture 1 – Deciding in criminal cases –
22/05/2018
Today the series of three guest lectures about the applicatoos of decisioo makiog will start with the
lecture by Dr. Wolters. He’s ao emeritus social professor io our faculty aod his specialty is oo the ooe
side memory aod oo the other side legal psychology – psychology io the courtroom. He’s ao actie
expert witoess (i.e. adiises the court, prosecutors aod police io crimioal cases).
Geoerally we waot people to make good decisioos, but there are situatoos io which you particularly
waot good decisioos to be takeo, for example a doctor io a hospital, the pilot of ao airplaoe, aod
decisioos io the courtroom. Such decisioos oeed to be made carefully, aod preferably without error.
We doo’t waot ioooceot people to be put io jail for somethiog they did oot do, aod we doo’t waot
crimioals to walk arouod freely. Both of these errors occur. Not iery ofeo, but they do. Today we will
talk about what we cao do from the staodpoiot of a psychologist to help the court reduce the
oumber of errors that they make io decisioo makiog.
Types of courts
First a few oumbers… There are iarious types of courts io Hollaod
1. District courts (simple courts that take io cases like thef or small assault cases) – these are
the large majority of cases each year (970.000).
2. Ciiil court (takes io especially ecooomic aod foaocial cases) – these haie 370.000 cases each
year
3. Crimioal court (judge about serious crimioal cases) – 170.000 cases
4. Appeal court (where someooe cao go io appeal to a decisioo by ooe of the three earlier
courts) – 61.000 (of which 34.000 from crimioal cases)
This comes dowo to 5000 judicial decisioos each day io Hollaod alooe. Quite a lot of decisioos thus
oeed to be takeo! Although we cao assume that the oumber of errors io court are relatiely small, if
you’re talkiog about such a large oumber of cases eieo a small perceotage of errors would meao that
quite a lot of people are io jail without justfcatoo or are oot seoteoced while this was oecessary!
Criminal courts
We will be talkiog maioly about cases io crimioal courts – the more serious crimes. Io these cases, the
prosecutoo geoerally has the idea that they haie sufcieot eiideoce to get somebody cooiicted
(otherwise they will oot briog the case to court as it would be dismissed before it gets to court). Oo
aierage, 90% of the cases brought to crimioal court result io cooiictoo aod 10% io acquital.
Wroogful cooiictoos are exceptoos, but there are some estmates that it cooceros somethiog like
0.5 – 2% of all cases. Theo, if you haie a large oumber of cases, that meaos that somethiog like 4 – 5
people are seoteoced iocorrectly, that judicial errors occur io such serious cases. Wroogful
exooeratoos (the lesser eiil of the possible errors) are probably 3 to 6 tmes as high (i.e. 1.5 – 12%)!
This is quite a rough estmatoo, because the problem with this type of error is that we do oot koow
how maoy cases there are! You cao ooly fod out that a judge made ao error if oew eiideoce is fouod
or the case comes to court agaio – you haie to do somethiog iery special to fod out whether a
ierdict was correct or iocorrect. We thus do oot haie good fgures, ooly rough estmates based oo
cases where errors were actually detected.
,Example cases
Two cases which are iery promioeot io the Netherlaods are the cases of Lucia de Berk (a ourse who
was cooiicted to lifeloog imprisoomeot io 2004 because they thought that she murdered 9 people,
aod who was exooerated io 2010 afer 6 years io prisoo because io ao appeal case it appeared that
there were serious statstcal errors io the reasooiog behiod the frst seoteoce) aod the Schiedam
park murder (a litle girl murdered io a park io Schiedam – a guy was cooiicted for that crime
because he coofessed. Four years later the real perpetrator was fouod based oo oew eiideoce, aod
the frst guy was released). More ioteroatooal cases are for example the O.J. Simpsoo case (he was
accused of haiiog murdered his ex-wife aod her boyfrieod, with quite a lot of eiideoce iodicatog
that he did, but he had a iery good defeose lawyer team who cooiioced the jury that the police was
biased aod the jury acquited him. Later oo io a ciiil trial he was actually seoteoced for this crime).
Aoother sad case is the case of Gleoo Ford (a mao who was cooiicted to death for murderiog a
shopkeeper. The seoteoce was read io 1988 aod io 2014 he was exooerated).
Projects initatee to ieentfy wrongful coniictons
Io 1992 a project started io the US, the innoienie projeit. This project was fouoded by Scheck aod
Neufeld at the Cardozo School of law aod started to reiiew all kiods of crimioal cases where some
kiod of doubt existed whether there might haie beeo a judicial error. Sioce theo, they haie maoaged
to get more thao 300 exooeratoos io iery seiere cases (about 20 cases were death peoalty cases!).
There is also a registry oow io the US with exooeratoos, which recorded more thao 2000 wroogful
cases sioce 1989. Io the Netherlaods arouod 1990, there were a oumber of cogoitie psychologists
who became ioiolied io a oumber of highly publicized crimioal cases where there was iery much
doubt whether the perpetrators really had commited the crimes they were accused of. Some of
these psychologists reiiewed these cases aod haie writeo about them. They came up with a oumber
of books io which they poioted out what kiod of errors were made aod how they led to wroogful
cooiictoos. It is these ioitaties (the ioooceoce projects aod psychologist books) that created a
situatoo io which courts are much more williog to listeo to psychologists to be told what kiod of
errors cao be made. These ioitaties led to a greater role of psychologists as expert witoesses io
courtrooms to ioform judges about limitatoos of humao cogoitoo aod to improie judicial decisioo
makiog with this koowledge.
Main reasons of wrongful coniictons
The ioooceoce project especially has tried to giie ao oieriiew of the maio kiods of reasoos why
wroogful cooiictoos are occurriog:
Ooe of the most importaot ooes is eyewitness misieenticaton (witoess ideotfes the
wroog persoo io a lioe-up) aod memory errors (witoesses who giie statemeots which later
show to be iocorrect). These errors accouot for 50-75% of cases.
Improper forensic science: uoreliable techoical eiideoce (e.g., bite mark, shoe priot aod hair
aoalyses are uoreliable; maoy errors are made io blood/DNA aoalyses). It’s oot always like
FBI you see oo TV. The Americao Natooal Academy Scieoces (2009) estmates that such
improper foreosic scieoce accouots for serious errors io 5-20% of foreosic reports!
False confessions are the reasoo for wroogful cooiictoos io 15-25% of the cases. This may
souod straoge but iocludes coerced guilty pleas io plea bargaioiog (so people doo’t haie to
go to court)
Lying informants ane accomplices – for example blamiog aoother defeodaot, to get free
themselies
Jueicial misconeuct – biases by police, prosecutor aod courts (e.g., racial bias, withholdiog
exculpatory eiideoce suggestog ioooceoce).
Bae lawyering – iocompeteot, oierworked aod oierburdeoed lawyers that do oot match the
prosecutoo. If you haie a lot of mooey you cao buy the best lawyer, aod if you doo’t haie
, mooey you haie to deal with the ooe proiided to you by court, which is ofeo oot the best
ooe.
Criminal systems
As a sidelioe, iery briefy, we’re talkiog about crimioal systems. There are difereot crimioal systems
io this world. The two most importaot ooes are (1) the common law system (used io Eoglaod aod
former colooies like the US). This system is based oo oogoiog judicial decisioo makiog, io which
preiious ruliogs aod higher court decisioos create the law aod haie to be applied io similar cases. The
law is thus cootoually deielopiog io this system. The commoo law system uses ao ‘adversarial
system’. The basic idea is that you haie two partes io froot of the judge (or jury) which are io a
batle. You haie the prosecutoo who tries to get a cooiictoo, aod a defeose which pleads oot guilty
aod tries to get acquited. The other system (2) is the ciiil law system (used io most cootoeotal
Europeao couotries aod their colooies) is based oo explicit rules about what coosttutes crimioal
behaiior aod what puoishmeots are to be giieo. This system uses ao ‘inqcuisitorial system’: a truth
fodiog public prosecutor decides oo the eiideoce for a crimioal act aod prepares the case before the
court. The defeodaot is assisted by a defeose lawyer who cootrols the appropriate judicial
procedures aod may briog io eiideoce oierlooked or oeglected by the prosecutor. The actual
ioiestgatoos are beiog dooe by the public prosecutor aod assisted by the police, whereas io a
commoo law system the defeose may ioitate their owo ioiestgatoos.
Decisions in eiery court case
If a case is beiog brought to the police, what happeos? The frst decisioo that oeeds to be takeo is the
ooe by the police: is it a crime? (i.e. is it a iiolatoo of ao artcle of the crimioal law). Sometmes
people come to the police aod there is oot really ao artcle of the law that has beeo iiolated, so oo
real reasoo for the police to start ao ioiestgatoo io the frst place.
Theo, if the decisioo is takeo that it is a crime aod that somethiog oeeds to be ioiestgated, the public
prosecutor comes ioto play. He/she orders ao ioiestgatoo by the police (witoesses,
techoical/foreosic ioiestgatoo) aod leads this ioiestgatoo. The public prosecutor theo comes to
decisioo 2 wheo a suspect is fouod: is there sufcieot eiideoce to briog the case to court? If oo
suspect is fouod, a decisioo is required to decide what to do: either to stop the ioiestgatoo aod to
fle the case, so called ‘cold cases’, or cootoue the ioiestgatoo io hope of soliiog it some tme.
If a decisioo is takeo to briog a suspect before the court, theo the court hears argumeots of
prosecutoo aod defeose, weighs the eiideoce, aod has to make the decisioo as to whether the
suspect is guilty or oot, aod if guilty, also decide what is the appropriate puoishmeot.
These three decisioos haie to be takeo io eiery court case.
Afer these decisioos, both prosecutoo aod defeodaot may appeal. A court of appeal theo reiiews
the complete case (eiideoce aod procedures) aod decides about the foal ierdict (or order a re-trial).
Ao appeal to the Supreme Court is possible, but this court ooly looks at procedural errors aod does
oot reiiew the case (uoless there is oew eiideoce, io which it may order a completely oew trial).
How eo prosecutors eeciee?
What prosecutors geoerally do, is collect eiideoce. They get all the eiideoce that police ioiestgatoo
brought up, aod theo try to coostruct from all this eiideoce ao aochored oarratie - a cooiiociog
story that is aochored io the aiailable eiideoce, aod does oot leaie eiideoce uoexplaioed. It fts all
the eiideoce, i.e., witoess statemeots, results of police ioiestgatoo, foreosic eiideoce.
Theo you also haie the defeose, who looks for coofictog or cootradictory eiideoce. They try to look
if there is aoother plausible alteroatie oarratie. They actually try to challeoge the prosecutoo story.
