PLANT CITY — A few weeks ago, Jason Hardwick's friends decided to tell him the rumor flying around town: Police Chief Steven Singletary was sleeping with his wife, Melissa.

Hardwick had to see it for himself. He attached a GPS tracker to his wife's car. On Jan. 12, as Melissa Hardwick was supposedly driving west to see a friend, Jason watched as the GPS showed where she was really headed — east, to Orlando.

Hardwick followed his wife's GPS trail, his father behind the wheel because he feared becoming too emotional. What he saw when he got to Orlando, and an ensuing city investigation, would end two police careers and threaten two marriages.

Singletary, 45, was officially fired Wednesday for using sick days and paid time to meet Melissa Hardwick, 35, for sex, according to a city investigation, charges which he denies. Another officer was fired for falsifying a report involving one rendezvous he witnessed.

Fallout from the affair has raised questions this week about another powerful city official. The Hardwicks, in videotaped interviews released by Plant City, said City Commissioner William "Billy" Keel tried to interfere with the city's investigation.

On Jan. 19, two days after the city suspended Singletary and launched an investigation, Keel — a close friend of Singletary's — texted a friend of Melissa's. Keel wanted her to tell Melissa to keep quiet about the affair, she told investigators.

"Did you see the text?" Assistant City Manager Bill McDaniel, the former police chief who led the investigation, asked Melissa.

"Yes."

"Can you tell us what it said?"

"That his (Singletary's) job depends on whether or not, I think it said, I testified."

Keel refused to answer questions Wednesday. He released a statement expressing confidence in the investigation and said he will not comment further.

"In my opinion, it is now time for the city to move forward," Keel wrote.

City Manager Greg Horwedel, who reports to Keel, said he has no plans to further investigate Keel's alleged overtures to Melissa Hardwick.

Keel's time on the City Commission began amid controversy.

After he was appointed by city commissioners in late 2012 to fill a vacancy, it was revealed Keel had business connections to two board members who voted for him.

Commissioner Rick Lott is a manager of Keel's company Matrix Medical and then-Mayor Michael Sparkman is a former business partner of Keel, according to state documents. Both Lott and Sparkman currently serve as commissioners. Attempts to reach them were unsuccessful.

Melissa Hardwick was familiar with Matrix Medical, she told investigators. Chief Singletary parked his city car outside the business several times last year when the two planned to meet. Hardwick then picked Singletary up and drove them to Lakeland, where they'd spend the day in a hotel.

Keel knew about the affair, Melissa Hardwick said, and had tried to convince Singletary to end it.

Singletary told his bosses the affair did not interfere with his work. Attempts to reach him have been unsuccessful.

"My private life should be my private life," Singletary told investigators. "It's clear that I made a mistake, but it was in my private life that I made a mistake."

Singletary met Melissa Hardwick at their gym more than three years ago, she said, and their families socialized as their clandestine romance developed. Jason Hardwick had suspected something, but it wasn't until his friends told him that he decided to investigate.

Melissa Hardwick was already inside the Orlando hotel by the time Jason Hardwick got there the evening of Jan. 12, he told investigators. She was having sex with Singletary, she said in one of two sworn interviews, which Singletary denied under oath.

Jason Hardwick and his father waited at a McDonald's for about two hours. When the GPS showed his wife moving again, father and son followed, to a Bahama Breeze restaurant.

"You two are a joke, have a nice life," Hardwick told them when he confronted them at their table. He took two photographs with his cellphone, and left. Minutes later, Singletary got a text message from his wife to come home. Jason Hardwick had sent her a picture.

Days later, Hardwick gave the chief an ultimatum by phone.

"I want you to resign and I want you to leave this town," Hardwick said he told Singletary. "I want you out of my town. … Maybe you can be a security guard at Sears."

The chief cried and begged forgiveness, Hardwick said. But when pressed on whether he'd leave, the chief was firm.

A few days later, Hardwick went to Singletary's boss and an investigation was launched.

After the confrontation at the restaurant, Melissa Hardwick returned to the hotel with Singletary, she said. But when she realized Singletary's main concern, she said she got mad and left.

"His job," she said. "He was more concerned about that … than he was about the fact that my husband now knows, and it affects our children and his wife and all of our families. He was only concerned about the plan for his job."

Times researcher John Martin contributed to this report.