Yeah, when you put it that way I think anyone could kill a kid and the say “oops, my bad,” get fired and then go on to another job and that would be the end of the matter.
As far as I am concerned, the Texas state AG should be in the loop on this. But I don't think the Tarrant County DA is going to drop the ball on this.
There was video of this that the police chief reviewed before he fired the police officer.
A Grand Jury will be more likely to indict now that he is a former police officer (in my opinion).