This paper compares estimates of the proportion of driver fatalities in which the driver is legally intoxicated from two data sources, accident reports and toxicological reports of blood alcohol concentration (BAC). A total of 1,260 driver fatalities in Texas had BAC test results available for study. Of the legally intoxicated driver fatalities identified by BAC tests, 68 percent of the corresponding accident reports did not show alcohol as a contributing factor in the accident. Descriptive statistics based on BAC results by age and sex of the fatally injured driver, and by time and date of the accident are reported. In addition, the underreporting rate of alcohol involvement is described by age and sex of the driver fatality, and by investigating officer (local police versus DPS). The findings emphasize the need for better quality data on alcohol involvement in traffic accidents.