Niles visited him , but the two had drifted apart .
Two years before the series began , Martin was looking forward to retirement when he was shot by a man named David Hicks in the line of duty after interrupting a robbery attempt in a convenience store .
Niles visited Martin , but the two had drifted apart .
Two years before the series began , Martin was looking forward to retirement when he was shot by a man named David Hicks in the line of duty after interrupting a robbery attempt in a convenience store .