CSI: Crime Scene Investigation, Season 9

Nick:
When I rolled up the passenger side window I found a cluster of impressions on the glass, no ridge structure. So, they're not fingerprints, they're knuckle prints. The stereo was turned down low, the only finger prints on the volume knob were Warrick's. If you've ever ridden with him, you'd know that he'd make your ear drums bleed. (Grissom silently laughs at the memory) So, volume turned down, knuckle prints on the glass, I think the killer knocked on his window.

Grissom:
(realizing) Well, Warrick would've never rolled down his window for Pritchard.

Nick:
No, no. Not after he just killed Gedda and was trying to frame Warrick for the murder.

Catherine:
Are we saying that it's not Pritchard?

Nick:
I think we are. ... McKeen. He's the only eyewitness. He's the one that placed somebody that looked like Pritchard in the alley. He's the one that is saying the suspect got into a vehicle with a partial plate that was a match to Pritchard's.