Who is Robert Joyner and what do Margo and Q have to do with the man?

One of Q's last memories with Margo occurred when the two of them found a dead man in a park. Q wanted to report the man to his parents and then the police. He surmises this is because he was "well-adjusted" due to the fact that both of his parents were therapists. But Margo wanted to investigate. Margo later learned that the man's name was Robert Joyner, that he was a lawyer, thirty-six and somewhat mentally disturbed. Apparently his divorce had pushed him to commit suicide.