It’s an episode in his life that Minnesota Gov. Tim Walz points to as the reason he stopped drinking. In 1995, Walz was a 31-year-old high school teacher living in Nebraska when he was pulled over for speeding, failed a sobriety test, and was arrested, according to court documents posted online two years ago by Alpha News, a conservative site based in Minnesota. He later pleaded guilty to reckless driving.

Since that night, Walz has served with the Army National Guard, rising to the rank of command sergeant major, won six Congressional races, and was elected to two terms as Governor of Minnesota. And now, Vice President Kamala Harris has picked him to be her running mate. Soon after Walz’ name emerged on Harris’ shortlist, supporters of former President Donald Trump began sharing details of Walz’ nearly 30-year-old DUI on social media.

In an 2018 interview with the Minneapolis Star Tribune, Walz described the episode as a gut-check moment. He had gotten married the year before. That night, he was driving home from watching college football with some friends. His wife Gwen Walz described to the Star Tribune how she told her husband after the arrest that now that he’s married, he has obligations and “can’t make dumb choices.”

The officer at the scene noted that Walz’s silver Miata was going 96 miles per hour in an area where the speed limit was 55. When Walz saw a car pull out quickly behind him, he sped up thinking someone was chasing him, Walz’s lawyer explained to the court. Walz stopped when the officer turned on the patrol car’s flashing lights.