[alcimedes]

I think it's a weird place to murder someone.

The most likely scenario (IMO) is that this individual did something, very, very bad in his past. Something that no one knew about.

Then he got elected, was on TV etc. and whatever it was from his past caught up with him. Someone said something, sent a letter, etc. that made him think his past was going to catch up with him and he killed himself rather than face it.

The fact that he died in his old high school parking lot would lead me to think it happened when he was in high school.

I'd still investigate it as if it were a murder though, because until you know you should be looking.