A candidate for Utah County sheriff has filed a complaint alleging that his opponent violated the law when a uniformed police officer was spotted putting up campaign signs.

Jim Phelps, a retired U.S. marshal, wrote in the complaint filed last week that he received a video showing a Pleasant Grove police officer taping up a campaign sign for his opponent, Mike Smith — the police chief in Pleasant Grove — at a business in American Fork. The officer’s patrol car is parked next to the business, according to still photos provided by Phelps’ campaign.

Phelps wrote in the complaint, which was released Thursday in response to a public records request, that the officer’s actions were in violation of Utah law, which prohibits government employees from participating in political campaigns while at work.

“Allegations of misdeeds by government officials are, at best, troubling,” Phelps said in a Thursday statement. “This notion that the ends justify the means could not be further from how it should be. This action is inexcusable, you have to fight corruption at all levels of government.”

Smith said Thursday that the first he had heard of the complaint was from reporters calling him for comment. He said police officers across the county are interested in the campaign but that he has made it clear to them that the rules must be followed.

He chalked up the complaint to a “campaign stunt” and said he hoped to focus more on debating the issues and what was best for the sheriff’s office.

“I don’t know what’s on the video,” he said. “But that’s not something we would condone, if it was happening. It shouldn’t be happening.”

Utah County Clerk-Auditor Bryan Thompson, who oversees elections, said Thursday that his office is investigating the complaint. If the allegations are true, he said, the Utah County Attorney’s Office will determine if any laws have been broken and what the appropriate response would be.

County Attorney Jeff Buhman declined to comment Thursday, saying he could not confirm whether his office was investigating.

Phelps and Smith are Republican candidates seeking to replace retiring Sheriff Jim Tracy. The next sheriff will be decided at the June 26 primary.