Gone (An Alex Delaware Novel)

I've read a few of the Alex Delaware novels, but years apart, so I have completely forgotten why Delaware, as a psychologist, gets to ride around with his detective friend all the time. It was an exciting story - I finished it in one day because I wanted to get to the answer. However, the immediate attention on the path that leads to the answer was odd. Also, there are searches that just wouldn't meet the requirements for the evidence to be admitted to court, which really bugged me. A bit gruesome, but the gross parts aren't dwelled on, so it didn't bother me too much.