The police gave the photo to the media in a press conference and said if you see him, call 911 and we'll "bring him to justice". Not entirely the media's fault. Dallas does have an active Hewey P Newton black gun club that frequently exercises their right to open carry. Tough to be a legal gun owner and be black these days. Where's the NRA? Where's the black gun rights matter?
Based on him showing up later on the ground after the shooting started, it seems like he was exercising his right to open carry in Texas. There's a Dallas based Hewey P Newton black gun club that does that sort of thing.
For exercising that right he gets his photo published in the media with a promise by the police to bring him to justice. Probably smart to turn himself in.
There was also the legal gun owner killed recently in Minnesota. Blacks' gun rights matter.