Because there's nothing more original than a "this time, it's personal" plotline. It goes without saying that there should be absolutely no way that DB would be within half a mile of the evidence in this case, but of course he's all over it. About the only think I really liked in this episode, other than Peri Gilpin's return, was Hodges' attempt to figure out the weird prints on the floor. And thanks to Bill Cosby, I know that Dr. James Naismith invented basketball.
Things get personal when Russell's son is a suspect in his coach's murder.
Other than that, eh. The sex therapist girlfriend? I only care if Lady Heather's involved.