I think Dog On It is one in a series of Chet and Bernie Mysteries. The unique thing about this book is that it's written in the voice of the dog, Chet. Chet flunked out of police K-9 School when his last test was infiltrated by a cat and he chose to chase the cat instead of the job. Now he works with Bernie, a divorced father of one, a sometimes heavy drinker, and in debt up to his eyeballs Private Investigator.
They set out to investigate a missing teenager but wind up tangling with the Russian mob in the desert of New Mexico. From the perspective of a dog, the story is very entertaining.
I think I'll check to see if the library has more Chet and Bernie Mysteries. I'd like to hear all of the details of flunking out of K-9 school!