A hair brush?
Why grab a hair brush during a traffic stop? That seemed very contrived here. So I figured it might based on a true incident, and sure enough it was, at least to some extent. In 2007, Khiel Coppin was holding a hairbrush when shot and killed by police who mistook it for a gun. But those circumstances were different than in this film. Coppin had a history of psychiatric problems was in a mentally unstable state when police arrived on scene.
Here is the news report on it https://www.nydailynews.com/news/crime/18-yr-old-carrying-hairbrush-shot-13-times-cops-article-1.260459