The Insurance Institute for Highway Safety (IIHS) publishes a list of fatality rates per 10,000 registered vehicles. In a report, the VW Jetta had a rate of 1.1 which was 21.4% lower than the Cadillac Brougham at 1.4. VW used this information in comparative advertising and claimed the reason for the difference was vehicle engineering. An in-depth analysis of the crash data indicates that the Jetta is inherently less safe than the Brougham and that the observed difference is primarily due to an older occupant age, a lower fraction of single-vehicle crashes, and lower belt use by Brougham passengers as compared to the Jetta.

If the Jetta fatility rate is adjusted to a comparable driver age and safety belt use as in the Cadillac Brougham, the Jetta has an adjusted rate of 2.0 which is 42.9% higher than the Brougham at 1.4. This difference is consistent with expected inherent vehicle rates based on the weight advantage of the Brougham. The analysis indicates the potential for misuse of field accident data, which are heavily influenced by driver and environmental factors. Inappropriate advertising may mislead the public and cause inaccurate perceptions of vehicle safety.