A recent instal­ment of Sci­en­tific American’s ’60-Second Psych’ dis­cusses a series of arti­cles on why inno­cent peo­ple con­fess to crimes they didn’t com­mit, and the prob­lems this can pose.

Sci­en­tists had 206 sub­jects wit­ness a “staged” crime and then were asked to pick the per­pe­tra­tor from a line up. They were later told that their choice denied the crime, and nearly 30 per­cent changed their iden­ti­fied pick.

But the great­est change occurred when par­tic­i­pants were told that another per­son, not the per­son they picked, had con­fessed to the crime. Now, 61 per­cent changed their iden­ti­fi­ca­tion, choos­ing the confessor.

On a related sub­ject (via Mind Hacks), another Sci­en­tific Amer­i­can arti­cle looks at how the brain makes judge­ments about crime:

The assign­ment of respon­si­bil­ity and the choice of an appro­pri­ate pun­ish­ment lie at the heart of our jus­tice sys­tem. At the same time, these are cog­ni­tive processes like many others—reasoning, remem­ber­ing, decision-making—and as such must orig­i­nate in the brain. These two facts lead to the intrigu­ing ques­tion: How does the brain enable judges, juries, and you and me to per­form these tasks? What are the neural mech­a­nisms that let you decide whether some­one is guilty or innocent?

[…] Until recently, such top­ics would have been out of the reach of cog­ni­tive neu­ro­science for lack of meth­ods; today, func­tional mag­netic res­o­nance imag­ing (fMRI) allows researchers to watch the brain “in action” as nor­mal human par­tic­i­pants make deci­sions about respon­si­bil­ity and punishment.