In two experiments, we tested the hypotheses that (a) the differences in nonverbal and verbal behaviour between liars and truth tellers will be greater when interviewees are instructed to maintain eye contact with the interviewer than when no instruction is given, and (b) instructing interviewees to maintain eye contact with the interviewer will facilitate deception detection. In Experiment 1, 80 mock suspects either told the truth or lied about a staged event and were or were not requested to maintain eye contact with the interviewer. The maintaining eye contact condition contained more cues to deceit than the control condition. In Experiment 2, 106 undergraduate students either watched or listened to a selection of the videotaped interviews from Experiment 1 and made veracity judgements. The request to maintain eye contact improved students' ability to detect deception in both Video + Audio and Audio conditions. The results of this study are compatible with other studies showing that placing greater cognitive demands on suspects increases the number of cues to deception and also of observers' ability to discriminate between liars and truth tellers.