I’ve been reading Christmasy Mysteries since 2005 or so when I found Crewel Yule by Monica Ferris and proceeded to read her whole Needlecraft series to that point, then I kept going with the new ones as they were released until the last of them . 
https://www.fantasticfiction.com/f/monica-ferris/needlecraft-mysteries/
https://cozy-mystery.com/monica-ferris.html

T’was the Bite Before Christmas
by David Rosenfelt
2023
Read by Grover Gardner 6h 33m
Rating – A / legal thriller
(#28 in Andy Carpenter Series)

And I started the David Rosenfelt books shortly after Ferris stopped publishing. Much to my delight, I love his books. He’s been writing the Andy Carpenter Mystery Series since 2008. That’s- 29 books including the new release scheduled for 2024.  I read the first one but was unimpressed, and then I found the first of the Christmas books, The Twelve Dogs of Christmas and I was hooked.  Later I tried another regular Andy Carpenter, a non-Christmasy one and was somewhat disappointed, so I stuck with reading a Christmas book as a personal tradition.

So what do I like about these little Christmas mysteries? Oh my – Rosenfelt writes Carpenter’s character and dialogue like he’s inside it. Rosenfelt’s  usually dry humor gets me laughing, even out loud sometimes. Another thing is the plots are twisty and there’s quite a lot of court action.  Andy Carpenter is a very rich private investigator but he takes on cases as they appeal to him. He is also an avid dog lover and has two dogs of his own, but has set up a foundation to provide temporary shelter for homeless dogs until he can find *good* adopted homes for them. He has a number of assistants to help with this – they call themselves Tara’s Friends. (Tara is the name of one of his own dogs.).

In this episode Christmas is coming (of course) and Andy’s wife, an ex-cop, is getting ready as she does every year starting at Halloween and then keeping the season going until February 1. Andy is enjoying the company of a few of Tara’s Friends associates when the police arrive to arrest one of them. It turns out Derek is not who he says he is. Derek is in a witness protection program but it looks like he’s murdered an old associate there.