Then why did he call the non-emergency number 911.
"This guy looks like he's up to no good, or he's on drugs or something. It's raining and he's just walking around." I'm not sure where the scary part is.
As somebody pointed out, if he was on the phone with somebody, he’s not going to be paying attention to everything around him. That can give the impression, to somebody looking at you from a distance the impression that you might be on drugs.
I also think that a possible reason why Martin might have given the impression that he was up to something is that, because he didn’t live in the complex, but was just visiting and may have been looking for something familiar to remind him where he was staying.
I’ve stayed in those sort of complexes and it can be disorientating.