(WOMENSENEWS)--Anti-choice truckers are displaying billboards of aborted fetuses as they drive in daily convoys along Southern California freeways. They maintain the First Amendment protects their rights of free speech to turn heads and cause near accidents.

Since it started a month ago, the grisly convoys have caused more than a few near misses, plenty of rubber-necking, vulgar gestures from pro-choice drivers and supportive victory signs from others, according to a report Thursday in the Orange County Register.

The truckers wear body armor and carry military-style helmets in their trucks, which are equipped with video cameras fore and aft. Off-duty police officers in unmarked cars escort the convoys, the Register said.

"We're a car culture here," campaign organizer Gregg Cunningham said of the "guerrilla marketing" conveys. "If people are going to live in their cars, that's where we'll go to engage them."

Each day at 6 a.m., the convoys depart from Santa Fe Springs at 6 a.m., loop through Orange County along Riverside, Costa Mesa and San Diego freeways before heading west into Los Angeles and the heart of Hollywood.

Cunningham, director of the Center for Bio-Ethical Reform, is a former assistant U.S. attorney and former Pennsylvania legislator.

Cunningham said the multi-million dollar campaign, funded by private donations, reaches about 400,000 people daily, many of them stuck in traffic and unable to escape the images.

"The freeway system is the last place where you can't turn the page or change the channel," he said.