First Time Ever

Ted Darling was about to kill a man. For the first time in his life...
You've never met a copper like Ted Darling. He's small, quiet. He doesn't smoke. He's packed in the booze. But he's a Specialist Firearms Officer. With black belts in four martial arts.
Then a shift in circumstances makes him swap guns for the CID. His first case is the brutal murder of a teenage girl. His new boss thinks he can wrap it up easily. Ted has doubts over the suspect.
Has he made the right choice in switching jobs? Or has he, as his Firearms boss warned him, committed career suicide?