Deck the hounds / David Rosenfelt.

Reluctant lawyer Andy Carpenter doesn't usually stop to help others, but seeing a dog next to a homeless man inspires him to give the pair some money to help. It's just Andy's luck that things don't end there. Soon after Andy's encounter with them, man and dog are attacked in the middle of the night on the street. The dog defends its new owner, and the erstwhile attacker is bitten but escapes. Andy's wife Laurie can't resist helping the duo after learning Andy has met them before... it's the Christmas season after all. In a matter of days Don and his dog Zoey are living above Andy's garage and become two new additions to the family. It's not until Andy accidentally gives away his guest's name during an interview that things go awry; turns out Don is wanted for a murder that happened two years ago. Don not only claims he's innocent, but that he had no idea that he was wanted for a crime he has no knowledge of in the first place. It's up to Andy to exonerate his new friend, if he doesn't get pulled into the quagmire first.