He was following the ******* so he could tell the police exactly where he was ? Not so he could confront him ?
No evidence has been shown that GZ intended to do other than follow TM.
Lots of speculation about what else he may or may not have been doing, but that seems to have all been based on wildly varying degrees of nonsense, such as how GZ couldn't name the street he is on, or using loaded terms like vigilante.
According to GZ, and TM's girlfriend, GZ was following TM. Again, according to the girlfriend, TM confronted (see how easy it is to use loaded words ?) GZ and asked him 'why are you following me?' and GZ responded 'what are you doing here?' and the next thing we have evidence of is TM on top of GZ and GZ yelling for help.
So - how did we get from 'why are you following me?' and GZ responded 'what are you doing here?' to shooting ? I would like those who are convinced that GZ is a vigilante and guilty as hell to help me understand what they think or believe may have happened.