Young unlicensed drivers are more likely to be in fatal crashes and to engage in high-risk driving behaviors like impaired driving, speeding, and driving unrestrained. In a crash context, the influence of these highrisk behaviors may spillover to adversely affect passenger safety restraint use. We conducted an analysis of the Fatality Analysis Reporting System from years 1996-2008. Fatal crashes involving a driver aged 15-24 years and at least one passenger aged 15-24 years were included. Logistic regression with generalized estimating equations was undertaken to assess the effect of unlicensed driving on passenger restraint use. We controlled for established predictors of passenger restraint use including driver restraint use, gender, number of occupants, driver drinking, number of occupants, crash year, and crash location (rural vs. urban). 102,092 passengers were involved in fatal crashes during the time period with 64,803 unique drivers. 6,732 (10.51%) were never licensed drivers and 5,603 (8.8%) were drivers with suspended, revoked, or expired licenses. Rates of unlicensed driving ranged from 17.7% to 22.1% and increased over time. While passengers in fatal crashes averaged a mere 40.9% restraint use, passengers of never and invalidly licensed drivers had a further decreased odds of wearing a safety restraint (OR 0.73, 95% CI 0.69-0.77, p<0.001) and (OR 0.84, 95% CI 0.79-0.90, p<0.001). Unlicensed driving is involved in a disproportionate and increasing number of preventable crash fatalities and plays a detrimental role in the lifesaving safety behaviors of their passengers. Our findings highlight an alarming peer influence between unlicensed drivers and passengers, placing increased emphasis on the need to better understand and characterize this present and growing threat.