Nearly 200 of the ads are running on the outside and inside of buses in King County, but you won't find them running on any buses in Snohomish or Pierce County.
"It's bad government on their part, quite honestly," said Ralph Fascitelli, president of Washington CeaseFire.
Gun control group Washington CeaseFire tried to put the ads on buses in King, Snohomish, and Pierce counties, but only got the green light in King County.
"This is a major public health issue," Fascitelli said. "We're a 501(c)3. We're not a political organization. We weren't espousing anything other than trying to get people to think twice about having a gun in the home."
In Snohomish County, Community Transit turned down tens of thousands of dollars in potential revenue by rejecting the ads even though, overall, ads only make up about 1 percent of its annual budget. Spokesman Martin Munguia cited a new policy this month banning ads about political and social issues.
"It's going to create a lot of angry people no matter which side you go on," Munguia said. "Rather than having debates take place on our buses and people get angry... we don't want to have that type of advertising on our buses."
Pierce Transit also rejected the ads, according to Justin Leighton, a spokesman there.
CeaseFire argues the bus ads were all statistics and statements about gun violence and have no graphic images. The group worries their First Amendment rights are being overshadowed by the debate on the Second Amendment.
Now, the group says it's considering suing.
"We have 30,000 people that die from gun violence every year," Fascitelli said. "Yeah, it's a hot button issue but it's also an issue we have to engage in a fair discussion about."
Munguia agreed there's a very passionate debate going on in the community about the issue. "So we're saying these are the types of ads we want to avoid," he said.
Metro Transit in King County has a policy similar to Community Transit's about no political issues on bus ads. This came under the spotlight in 2010 with some controversial ads about violence in the Middle East. But despite its policy, Metro says these new ads about gun control passed the test.
Metro had two complaints since the ads started running on May 8, said Jeff Switzer, a Metro spokesman.