Expert credentials and scientific validity of expert evidence have been shown to impact mock jurors' perceptions of expert credibility. The current study investigated the interactive effects of these two variables. Participants (N = 273) were exposed to a mock civil trial based on a real hostile work environment case. We were interested in both the interactions of expert degree and overall validity of the evidence, as well the impact of degree with specific types of validity. In a between-subjects design, we varied the expert's educational degree (MS vs. PhD) and the scientific validity of the expert's evidence through internal validity (high vs. low) and ecological validity (high vs. low). Results indicated an interaction of degree with overall scientific quality, while controlling for participant sex. When the expert presented high-quality testimony, a PhD expert and their evidence were perceived more positively than an MS expert.