AURORA, Colo. -- There is a free speech controversy involving an Aurora police officer after a driver said his bumper sticker got him pulled over and ticketed.

Paul Wansing's ticket was for a cracked windshield, but he believes it was his "Legalize Marijuana" and "Impeach Bush" bumper stickers that were the real problem.

Wansing said many people have windshields with cracks in them and none of them are targeted.

"The issue at hand is free speech," he said. "My mission is to let people know that free speech is being violated by certain members of law enforcement."

This past week, Wansing was pulled over on Alameda near Interstate 225 by an Aurora police officer who cited him for two minor violations.

The cop said that an air freshener obstructed the windshield and that a relatively minor crack made for an unsafe vehicle. But the officer also openly criticized the vehicle's pro-pot sticker.

"He didn't feel his children should have to look at that 'trash,'" Wansing said.

The officer admitted saying he was offended by the sticker, but police say that's not why the truck was stopped.

"The number of stickers, I guess, attracted the officer's attention to the truck, and this is when he saw the violations," Aurora police spokesman Rudy Herrera said.

Proponents of a statewide vote to legalize pot call it intimidation.

"The anti-marijuana madness has got to end," said Mason Tvert, with Safer Alternative For Enjoyable Recreation (SAFER), the organization trying to legalize marijuana statewide.

Officers have a lot of discretion over whom they pull over. SAFER wants the attorney general to order all police officers not to pull over people for expressing a political view about pot.

SAFER still needs to gather about 68,000 signatures before it can put the statewide proposal to voters. The exact wording on the petitions will be finalized next month.