The 22-by-7-foot billboards sit on two trucks belonging to the Center for Bio-Ethical Reform, a non-profit group based in Los Angeles, The Austin-American Statesman reported Wednesday.
Despite complaints from residents the billboards are too graphic, police say they can't do anything about them. A city ordinance that prohibits moving billboards applies only to those displaying for-profit advertising.
In addition, Austin City Attorney David Lloyd says the vehicles aren't considered mobile billboards if they advertise messages directly related to the vehicle owner's business.
In this case, the Center for Bio-Ethical Reform owns all of its trucks and is displaying its own message, he said.