Abstract
In a repeated-measures experimental study, we examined how evidence type influences police investigators’ beliefs about (a) suspect’s culpability and (b) the reliability of incriminating evidence. South Korean police detectives on active duty (N = 202) read four reports with different critical information pointing to a suspect. We manipulated the critical information by swapping out the pieces of CCTV, DNA, fingerprint, or eyewitness evidence. Hence, the inculpatory information delivered by each type of evidence was identical and given to the participants on the same level. Consequently, we found that—at an early stage of a criminal investigation—evidence type influenced a police detective’s judgments about suspect’s culpability and evidence reliability. Our findings are interesting in that when the same criminal fact is exhibited in different forms of evidence, it can result in participants’ different investigative judgments. Theoretical and legal implications of these results will be discussed in the paper.
Keywords: Evidence Perception, Evidence Reliability, Police Investigation, Investigative Decision-making, Evidence Type.