According to an eyewitness, the shooter used his car to drive into a group of protestors, then opened fire shooting a protestor three times and killing him and then the shooter immediately called 911 claiming he was the victim and feared for his life under the Texas stand your ground law:
https://www.cnn.com/videos/us/2020/07/27/austin-armed-protester-shot-and-killed-during-blm-march-cuomo-cpt-vpx.cnn
https://www.cnn.com/videos/us/2020/07/27/austin-armed-protester-shot-and-killed-during-blm-march-cuomo-cpt-vpx.cnn