During the war Griff was an ordinary officer who did not much care about gangs or crime. He wanted his money and a good time, and made no secret of it.
He started noticing what the violence was doing to the people around him, and grew popular almost by accident. When Kato found him and pitched a new Genesis City, Griff turned it down. He did not want the responsibility.
Then he lost his partner. The last thing that partner told him was that he was capable of more than this and had to take a stand. He joined Kato, and became the difficult, unserious cop the city knows now.
Five years ago he found an ape on the Docks and, for reasons he has never fully explained, took him in. They became friends once Griff realised the ape had no memory of his own past. He promised to help him get it back, and told him to use the enormous amount of Alpha he was carrying to help people. He considered putting him forward for the League. The ape refused, saying he would do more good where the League was not looking.