The Science of Perception and Memory:
A Pragmatic Guide for the Justice System

Oxford University Press, 2014

Prof. Dan Reisberg

reisburg portrait

Photo by Darryl James.

Eyewitness testimony is the bedrock of the American justice system. When a witness picks a suspect out of a line-up or points to a defendant in a courtroom and says, “He did it,” the jury is duly impressed.

But our memories are anything but airtight. They are vague, porous, plastic, and fallible. Sometimes, without realizing it, we are capable of manufacturing false ones—a finding with dramatic implications for the courtroom. 

Prof. Dan Reisberg’s [psychology 1986–] book begins with an introduction to science and research psychology, including a discussion of the admissibility of scientific research and expert witnesses. The subsequent chapters are divided by topics such as perception, memory, confessions, understanding the difference between lies and false memories, and children’s memories, with a particular focus on how children remember and report abuse.

Reisberg’s intent is not to invalidate the importance of eyewitness testimony. Throughout, he argues there are many instances in which our memories can be false, incomplete or fallible. But there are also times when a witness’s credibility can be strengthened by scientific research. If you’ve never been an eyewitness but now wonder about the memory of that conversation you had with your friend last week, worry not. “Human perception is generally accurate (and, in fact, rather precise),” Reisberg writes. “Likewise, human memory is, in general, relatively complete, long-lasting, and correct.”


The Oregon Supreme Court recently overhauled the state’s standards for eyewitness identification and granted a new trial to a man convicted of murder on the basis of a faulty eyewitness identification.  The justices’ ruling relied, in part, on testimony from Reisberg, who frequently serves as an expert witness on perception, memory, and the ability of a witness to correctly remember events, faces, and conversations.

Reisberg worries that the legal system’s adversarial nature may cause some to receive his book with skepticism, but he hopes “that everyone in the justice system wants to maximize the quality of the information being considered and to seek ways of distinguishing good information from bad.”   

—Amanda Waldroupe ’07