Bloodhounds/Diamond Dust by Peter Lovesey

THE BLOODHOUNDS
The Bloodhounds of Bath is a society that meets in a crypt to discuss crime novels. To their latest recruit they are simply a gaggle of dotty misfits, until one of them reveals that he is in possession of one of the world's most valuable stamps, recently stolen from the Postal Museum. Then theft is overtaken by murder when the corpse of one of the Bloodhounds is found in a locked houseboat, with the only key in the possession of a man with a perfect alibi.
DIAMOND DUST
With another court case over and a local villain banged up for a few years, Detective Inspector Peter Diamond is keen to get his teeth into another case. So when a call comes in that a woman's body has been found in one of Bath's parks he gets himself to the scene in record time, where he is able to identify the victim as his wife and to establish the fact she's been shot. Mad with grief, Diamond eventually concedes he cannot be an unbiased member of the investigation. Keeping himself away from the team becomes all the harder when he suddenly finds himself under suspicion, and when his colleagues find no case against him but appear unwilling to follow up any of his suggestions - did Steph's previous husband have an alibi - Diamond decides that a little independent action is called for.