LARGO — Fire Chief Mike Wallace, the subject of an internal city investigation for weeks, announced Monday that he plans to retire April 1.Wallace said he is a victim of frustration, lack of trust and poor morale among firefighters who endured layoffs and stagnant salaries in recent years. With pension cuts on the horizon, firefighters blamed him for failing to stand up for them during budget time, he said.Wallace finally decided to leave."It was more important for me to allow the city and department to move forward without the distraction of political infighting," he said. "I would never have recovered from this no matter how it played out."Largo City Manager Mac Craig said he could not discuss details of the investigation, which should be completed later this month. But he said that Wallace is not accused of doing anything illegal or immoral. City investigators, he said, have asked more than 50 people about two issues."It only dealt with telling us your thoughts about leadership and morale," Craig said.Most of those interviewed, he said, had similar things to say."I hated to do this," Craig said. "As far as I'm concerned, he's a fine, upstanding gentleman and always will be."Wallace, 57, took over the Largo department in October 2007. It was a kind of homecoming for him. Although he began his career in 1982 as an emergency medical technician with the Madeira Beach Fire Department, he moved to the Largo department in 1986. He served as a lieutenant, district chief and division chief over the next 18 years, until he went to Seminole as that city's assistant chief. Three years later, he returned to Largo.Wallace followed a chief who had been the subject of two investigations. One concluded Jeff Bullock had used his position improperly to get a discount on a bed topper for his personal pickup. The other was sparked by claims from a firefighter that Bullock had mismanaged the department and mistreated employees. The city closed that investigation after finding no proof Bullock had violated Largo's discrimination and harassment policy. Karry Bell, the acting chief after Bullock departed, also resigned while under investigation. He said he was the victim of a flood of complaints by firefighters. Wallace's tenure did not prove peaceful. The county plunged into a debate over the way emergency medical services are provided and the cost of the service.And Largo, like most local governments, faced hard financial times when the real estate market crashed. The city responded by taking away firefighters' raises, laying off firefighters and looking at pension reductions. Wallace saw his job as supporting whatever Craig and the City Commission decided. Firefighters saw it differently, he said.Firefighters saw it as "the city was taking and taking and taking and the fire chief didn't do anything about it," he said.Complaints soon began about weak leadership and poor morale."This is a culmination of a growing frustration," he said.