This study examined how using ground rules influenced recall and suggestibility to leading questions in elderly eyewitnesses. A 2 (age group: younger and older adults)×2 (ground-rule instructions: instructed and control) between-subjects factorial design was used. Participants were older adults (n＝61, Age range 65–75 years) and younger adults (n＝66, Age range 25–35 years). Participants in the ground-rule instructed group received a pre-interview explanation outlining the conversational ground rules of the interview including explicit permission for participants to say “I don’t know” when appropriate, whereas those in the control group received no such explanation or instructions. Results indicated that older adults correctly recalled fewer items under free recall than younger adults. Suggestibility to leading questions, on the other hand, was significantly higher in younger adults than in older adults. The provision of ground-rule instructions decreased the amount of incorrect recall and suggestibility to leading questions in all age groups. These results confirmed the effectiveness of the provision of ground rules in different age groups.
