The right to resist wrongful arrest
http://dovelove.wordpress.com/2007/09/19/it-is-every-citizens-duty-to-resist-false-arrest/
http://www.constitution.org/uslaw/defunlaw.htm
People (especially Americans): You have the right to resist unlawful arrest. You have the right to defend somebody being unlawfully arrested.
Wrongful arrest = assult and battery.