When an Alibi Is Not Enough: Judgments of Evidence Needed to Lay Charges in a Burglary Case

Laypersons were asked to assume the role of investigators to explore judgments of what evidence is needed to make an arrest in a criminal investigation when an alibi witness is present. Participants were sensitive to the relationship between the alibi witness and the suspect and were more likely to believe an alibi provided by someone unrelated to the suspect, as evidenced by requests for more physical evidence against the suspect than when the alibi corroborator was a family member. In addition, when presented with contradictory evidence, the age of the alibi witness became an important consideration. Age alone did not impact perceptions of evidence adequacy; however, when an (adult) eyewitness provided testimony that contradicted a child alibi witness, participants demonstrated partiality towards believing the child as evidenced by (a) more requests for physical evidence to be convinced the child was wrong and to arrest the suspect and (b) higher ratings of alibi witness credibility. This effect was not seen when the eyewitness’s testimony contradicted an alibi provided by an adult. The results provide insight for investigators and legal counsel regarding the influence of varying types of alibi witness evidence.