Casey stands there and furrows her brow at Rook for about five hours. I hope the court stenographer got it all.
Since Casey has a hard time with airtight cases, it's pretty clear she's not going to be able to win with doubtful evidence, and when Rook delivers an effective closing argument in which he urges the jury not to just blindly follow orders, Casey's done for. Not to mention you couldn't turn on NBC for the past week without seeing a maniacal Robin Williams with a captive Olivia Benson, so we're all just waiting for the last five minutes anyway, aren't we? Rook's found not guilty, thanks the jury, and hugs Casey ("back off!" snaps Elliot). He runs off, presumably to the cultural crimes against humanity court, where Man of the Year, RV, and License to Wed may be tipping the scales in favor of the death penalty.
So the next day, Rook's all over some crappy morning talk show with his pet sheep (named Elliot, much to Stabler's consternation), since he's becoming a folk hero with his anti-authoritarian views, and his supporters are having a rally in Bryant Park. "Let's go crash his party," says Olivia, and this is where Cragen probably ought to say, "Instead of harassing people found innocent by the courts, maybe you could work on actual cases," but he doesn't say anything.
Shit, even Casey tags along (guess she's got nothing better to do either) to this improbable rally, where hundreds of people have mobilized in support of a guy who was charged with sexual assault, and Rook yells at everybody to embrace chaos. And apparently everyone knew to bring pillows, which they cut open and litter the air with down. Yes, nothing says "I embrace chaos" by participating in a planned, synchronized pillow-tearing. Elliot almost looks like he's enjoying himself. And -- there's Munch in the crowd, anti-sheep button pinned to his jacket, gleefully taking part in the pillow fight.
Back at the station, Munch (rolling a lint brush over his suit) tells the other detectives that they got Rook wrong; that his phone calls were not about sex but about the importance of questioning authority. "I don't condone what he did, but I understand where he's coming from."