Megan Barry has stepped down as Nashville's mayor after she pleaded guilty Thursday to felony theft of property over $10,000 related to her affair with former police bodyguard Sgt. Rob Forrest.

She agreed to reimburse the city $11,000 in restitution, and serve three years probation.

Former Nashville Mayor Megan Barry's mugshot.
Barclay, Thomas

Sgt. Forrest also pleaded guilty Tuesday to criminal theft after an investigation by the Tennessee Bureau of Investigation into their affair. He agreed to pay $45,000 restitution to the city.

Sgt. Rob Forrest

Barry announced her resignation at a brief news conference Tuesday morning. Vice Mayor David Briley is now the acting mayor of the city, but will not officially be sworn in as mayor.

MORE: Meet David Briley, Nashville's new acting mayor after Megan Barry's resignation

"My time today as your mayor concludes," Barry announced this morning. " My unwavering love and sincere affection for this wonderful city and its great people will never come to an end."

"I love you Nashville," she concluded.

Barry's exit comes after she admitted Jan. 31 to a nearly two-year affair with Forrest, who retired that same day. Barry is the subject of three investigations, including a criminal inquiry by the Tennessee Bureau of Investigation at the urging of District Attorney Glenn Funk.

Forrest retired that same day after over 31 years with the department.

He earned over $170,000 in overtime pay during Barry's time in office, more than the combined amount of the other officers on the security detail.

The former mayor called close advisers this morning to inform them of her decision, according to multiple sources.

Barry, a Democrat, was the first Nashville mayor to leave office before the expiration of their term in nearly a century.

Lt. Governor Randy McNally weighed in on the news, saying it was a "sad day for all of us."

Tennessee state Senator Ken Yager (R- Kingston) was the first lawmaker to acknowledge the announcement on Twitter.

Related to the guilty plea, an affidavit filed with the warrant said nude photos taken from the phone of Forrest are evidence Barry engaged in the affair while he was on duty. Barry repeatedly denied that their romantic interactions took place while Forrest was on the clock.

The photos are referenced in an affidavit in support of a search warrant that Nashville Judge Steve Dozier signed seeking access to the contents of Barry's cellphone. It was filed in the Criminal Court Clerk's office, and Barry's attorney said he provided the pass code to the mayor's personal cellphone to the TBI days later.

Barry's exit comes after she admitted Jan. 31 to a nearly two-year affair with Forrest, who retired that same day. Barry is the subject of three investigations, including a criminal inquiry by the Tennessee Bureau of Investigation at the urging of District Attorney Glenn Funk.

The scandal took a more severe turn for the mayor late last month after an affidavit detailed nude photos that TBI investigators said appeared to be Barry taken on the phone of Forrest during city trips. They also highlighted hundreds of deleted phone chats on Forrest's phone. In a search warrant seeking possession of Barry's phone, agents said they had evidence that two state crimes were committed.

Increasingly, Nashville's political leaders have expressed frustration about the scandal, calling it a black-eye on a city that has raised its national profile. As her administration navigated the scandal's fallout, it became more difficult to focus on daily government business, observers said.

Those sentiments hardened after a report by USA TODAY NETWORK-Tennessee showed Forrest racked up racked up hundreds of hours of overtime in Nashville, escorting the mayor to hot yoga classes and hockey games, late-night concerts and trendy restaurants. The review found, in some instances, there were no events on Barry’s calendar during hours Forrest earned overtime pay.

The Tennessean's Editorial Board called for her resignation in a stinging opinion column published on February 28.

A former at-large councilwoman elected in September 2015, Barry was a favorite among liberals, whose popularity only expanded after taking office. Even after admitting affair, a new Vanderbilt University poll found her with job approval from 61 percent of Nashvillains, although that poll concluded prior to the explosive revelations detailed in the TBI affidavit.

Barry, 54, oversaw a business-friendly, socially-progressive agenda and was known for her accessibility — an exceedingly social mayor who was regularly seen at sporting events, ribbon-cuttings, parties and other events.

The last Nashville mayor to leave office before their term expired was in 1923 — decades before the formation of Metro government — when Mayor Felix Z. Wilson was kicked out of office by the Nashville City Council.

The council no longer has that power, but multiple council members had been looking at a non-binding resolution that would have called for Barry's resignation.

Barry's political career was abruptly upended on Jan. 31, when she admitted to engaging in an affair with Forrest, the head of her security detail and a 31-year officer on the Metro Nashville Police force. Both Barry and Forrest are married, but Forrest's wife has filed for divorce.

Barry's admission — in an interview with the USA TODAY NETWORK – Tennessee and then alone on a city hall stage before a scrum of media — shocked the city and set into motion a series of investigations into whether she had violated ethical or criminal laws. She apologized for her personal failings.

Forrest, 58, served as the leader of the mayoral security detail for 14 years. He maintained that role from the time Barry entered office in September 2015 until his retirement, which took effect the same day Barry acknowledged the affair.

The affair began sometime in spring 2016, Barry said. She refused to say when it ended, but said when she announced the affair that it was over.

Former Mayor originally denied any legal wrongdoing

The TBI confirmed it was investigating whether Barry or Forrest misappropriated public funds or engaged in official misconduct. The TBI subpoenaed Forrest’s city-issued cell phone and other evidence from the Nashville police and obtained documents from the mayor’s office.

But the TBI affidavit filed with a search warrant on Feb. 22, listed two possible criminal violations. The affidavit cites state statutes for misconduct of public officials and employees and theft of property.

While the former mayor denied violating any laws or policies, documents released by the city in the days following Barry’s admission show multiple potential problems.

Forrest was the only city employee on at least 10 taxpayer-funded trips with Barry from the middle of 2016 through 2017 — a period in which the couple were having an affair.

On trips to San Francisco, Kansas City and Athens, Greece, Barry admitted to staying extra days, accompanied by Forrest, beyond the time she needed to attend conferences, tours or other official reasons for the travel.

Barry routinely traveled without security before June 2016, records show. Her office gave various and at times conflicting answers to explain why she didn’t need security on earlier trips but did on others.

In October 2016, the mayor’s office assumed responsibility for approving and paying for travel expenses for Forrest as well as other members of the former mayor’s security detail.

The former mayor’s chief of staff was designated as Forrest’s supervisor in the city’s computerized travel request system. After that change, Anderson — who ultimately was Forrest’s supervisor — did not receive automatic notice of any travel requests for Forrest or other members of the her security detail, although his signature was automatically generated by the computer system as approving the travel.

With Barry’s resignation, Briley to assume mayor's office

Briley won’t be officially sworn in as mayor, but he will earn the office’s $180,000 salary.

Under the Metro Charter, the election to replace Barry will take place during the Aug. 2 general election. A run-off election between the first and second finishers will occur in September if no candidate garners at least 50 percent of the vote.

Barry’s resignation would have triggered a stand-alone special election if the next city general election was more than one year away.

The council’s speaker pro tempore, Councilwoman Sheri Weiner of Bellevue, will serve as vice mayor in Briley’s absence.

Briley, elected as vice mayor in 2015, ran unsuccessfully for Nashville mayor in 2007. A Democrat known for his progressive politics, Briley is a strong bet to run for the office full-time in August.

Other potential candidates include Nashville businessmen Bill Freeman and David Fox, who both lost to Barry in the 2015 mayoral election.

Barry's rise to prominence

Barry is married to Bruce Barry, a Vanderbilt University professor and columnist for the Nashville Scene. In July, the couple’s only son, Max, died due to a drug overdose, catapulting the former mayor to become a national voice in the fight against opioids.

Although Barry had sky-high approval ratings in office, her policy agenda hit road blocks recently with the collapse of the Cloud Hill project to redevelop Greer Stadium and her unexpected proposal to end inpatient services at Nashville General Hospital.

The scandal forced Barry to take a backseat in the biggest political fight of her career — approval May 1 for a referendum on raising four taxes to pay for a $5.4 billion transit plan.

A favorite of Nashville progressives, Barry overcame a sizable fundraising advantage against six opponents to make the mayoral runoff in September 2015, where she defeated Fox.

During the campaign, she embraced the pro-business politics of her predecessor, Karl Dean, adopting a campaign of "Keep Nashville moving forward" — a nod to the unprecedented economic growth of the city.

Before broadening her coalition with support from Nashville's business community, Barry was seen foremost as a social liberal. As a councilwoman, she sponsored Metro's first non-discrimination ordinance for city employees who are gay, lesbian or transgender. In 2015, Barry officiated over the first same-sex marriage in Nashville history.

Barry, who moved to Nashville in the early 1990s to attend graduate school at Vanderbilt University, worked in corporate ethics before becoming mayor, most recently at the Charlotte, N.C.-based health care company Premier.

Tennessean reporter Natalie Neysa Alund contributed to this story. Reach Joey Garrison at 615-259-8236, jgarrison@tennessean.com and on Twitter @joeygarrison. Reach Nate Rau at 615-259-8094 and nrrau@tennessean.com. Follow him on Twitter @tnnaterau.