Well, not the chickens themselves, per se, but rather their keepers. Apparently if you drive your permiculture bus/house to Minnesota to spread education and goodwill, that makes you subject to search and seizure, under the most dubious of circumstances.
Thanks to Lisa Z for this week's bit of deeply alarming (and subverted) news. See the story at her blog.
Perhaps local law enforcement was afraid they'd show up with eggs and rotting vegetables to throw at the RNC? Really, now.