Dubious Justice (Justice Series Book 11);

DS Lorne Warner and DI Katy Foster are called to the scene of an electrician's suspected suicide but quickly discover that they're dealing with a murder case instead.
Katy's family emergency forces her back home to be by her parent's side in Manchester, leaving Lorne as detective inspector, working alongside a new, and frustrating, partner.
When two more murders of tradesmen occur, the investigation throws suspicion on a couple who have recently renovated their home. However, the forensic team uncovers a lot more than anyone bargained for.