CLACKAMAS, Oregon - February 28, 2010 - When Robert J. Ekas decided to exercise his right to free speech, he didn't open his mouth. He hoisted his middle finger.

His single-digit protests, aimed at Clackamas County sheriff's deputies last year, resulted in verbal showdowns, traffic tickets and ultimately a federal lawsuit.

Giving a police officer the finger may be a rude and ill-advised gesture, but it is not against the law, legal experts say.

"The U.S. Supreme Court has consistently held that speech may not be prohibited simply because some may find it offensive," said Ira P. Robbins, a law professor from American University in Washington, D.C. "Virtually every time someone is arrested for this, assuming there's no other criminal behavior... the case is either dismissed before trial or the person is convicted at trial and wins on appeal."

Ekas, who represents himself, sued the Clackamas County Sheriff's Office and three of its employees, seeking corrective action and unspecified damages. Assistant County Counsel Edward S. McGlone III declined comment on the lawsuit.

Ekas, 46, a retired Silicon Valley systems analyst turned mathematician who lives in the Clackamas area, claims the traffic stops were acts of retaliation that violated his First and Fourth Amendment rights. He also wants the court to rule that the Sheriff's Office fails to discipline employees who "chill citizens' free speech rights."