FARGO (AP) - An Oregon truck driver and activist is suing the city of Fargo in federal court over a $60 ticket he got for having obstructed windows in 2004.

Robert Rudnick, of Bend, Ore., refers to the minivan he was driving as a "Truth Van." Pictures of aborted fetuses covered the rear-side windows and back window.

Rudnick's civil lawsuit alleges city regulations were too vague and that the city violated his constitutional right to freedom of speech. The lawsuit seeks an order barring Fargo from enforcing its obstructed-windows ordinance against Rudnick.

"Certainly we don't feel that we've done anything improper or illegal here," said Mike Miller, Fargo's assistant city attorney.

The city ordinance prohibits people from driving vehicles with windows covered by frost, signs or other "nontransparent material." A second section bars drivers from operating vehicles with material or tinting unless it transmits a certain amount of light or unless the vehicle has acceptable rearview mirrors on the outside.

Rudnick's attorney, Peter Crary, believes the sections are contradictory. He said Rudnick's van has acceptable mirrors.

Court papers say Rudnick would like to drive his van in Fargo in the months before the 2008 general election.