CSI, Season 4, Episode 5 "Fur and Loathing"
Plot Summary: A man dressed in a full raccoon suit becomes roadkill after he's hit by a car on a dark stretch of highway. When Grissom and Catherine arrive, they discover he has also been shot. During the investigation they find that He's part of a group of people called "Furries".
Written By: Jerry Stahl
Directed By: Richard J. Lewis
Here is a thread on the CSI Guide.com website about this episode
And here is some wonderfully well written observations about the episode written by PeterCat