In more than 25 per cent of wrongful convictions
exonerated by DNA testing, innocent defendants made incriminating statements,
delivered outright confessions or pled guilty, according to the Innocence

Police interrogation tactics – which include exaggerating
the evidence against the suspect or implying the suspect could face an extreme
sentence – can prompt a suspect to make a false confession, said Daniel
Lassiter, an Ohio
University professor of

In videotaped confessions, many law enforcement agencies
focus the camera on only the suspect. Lassiter’s research shows that this
practice creates what he calls a camera-perspective bias that leads trial
participants to view the confessions as voluntary, regardless of how interrogators
obtained them.

In the recent study, published in the March issue of
Psychological Science, Lassiter and colleagues from Northwestern University
and the American Bar Foundation asked 21 judges and 24 law-enforcement officers
to view a videotaped mock confession.

The researchers presented participants with different
versions of the confession in which the camera focused on only the suspect,
only the detective, or both suspect and detective. Participants assessed how
voluntarily the suspect confessed in each case.

The study found that judges and law enforcement officers
considered the suspect-focus version of the confession to be more voluntary
than the equal-focus and detective-focus versions.

“The phenomenon (camera-perspective bias) is rooted in a
naturally occurring perceptual bias that affects everyone and which cannot be
readily overcome regardless of people’s expertise or the amount of professional
training they have received,” Lassiter said.

Though some in the legal field have been skeptical of
such research, this study’s use of judges and law enforcement officers as
participants demonstrates the real-world relevance of the work.

“It’s a challenge in psychological research to move in a
persuasive way from the laboratory setting, and this is an important next step
that builds on the long program of research that Dr. Lassiter pioneered,” said
Shari Seidman Diamond, Northwestern University Howard J. Trienens Professor of
Law and co-author of the paper.

Lassiter’s two decades of videotape interrogation
research have led to changes in law enforcement policy. New Zealand, Wisconsin
and Virginia, as well as the Innocence Project, a nonprofit organization
dedicated to exonerating wrongfully convicted people through DNA testing, have
used his work to push for amended regulations.

Lassiter hopes his research eventually will influence wider legislative
reform that would require equal-focus videotaping.