A recent study in the journal Psychological Science shows the way videos are produced can subtly trick viewers into thinking the confessions are voluntary depending on whether the video focused on the suspect or detective.
… 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.