Interested adults, such as parents and attorneys, may pose as safeguards against juveniles' vulnerabilities during custodial interrogations; yet, the trial-level ramifications of their presence are unknown. The current research examined mock jurors' perceptions and case decisions after they read about disputed juvenile confession evidence elicited in the presence of an interested adult. We hypothesized that when reading about a voluntary confession (vs. coerced or none), participants would be more likely to convict, find the defendant vulnerable, and view his interrogation less negatively. When an interested adult (parent or attorney) was present, we anticipated an increase in convictions, lower vulnerability perceptions, and less negative views of the interrogation, and especially so when the adult encouraged the juvenile to speak. Jury-eligible participants in Study 1 (N = 435) and Study 2 (N = 673) read a case about a 15-year-old male charged with murder and then completed a post case questionnaire. We manipulated confession type (coerced, voluntary, none) in both studies, interested adult's mere presence (parent, attorney, no adult) in Study 1, and adult advice (parent/attorney prompting the defendant to keep quiet or speak) in Study 2. Overall, findings demonstrated higher conviction rates when there was a voluntary confession (vs. coerced or none). Study 1 revealed that a parent's or attorney's presence inflated conviction rates, and Study 2 demonstrated that adults' advice did not affect convictions or perceptions. Interested adults' presence during juvenile interrogations seems to legitimize confession evidence instead of protecting juveniles at the trial level. (PsycInfo Database Record (c) 2020 APA, all rights reserved).