This year’s race for Fairfax County sheriff has taken a lively turn into the normally sleepy complexities of pension benefits, with Republicans saying Democratic incumbent Stan G. Barry could unfairly collect about $1 million if he wins a fourth term.

Republicans accuse Barry, 53, of gaming the pension system by enrolling in the county’s Deferred Retirement Option Program, known as DROP, so that he could amass a lump sum retirement benefit of about $1 million — and then keep on working.

The GOP accuses Barry of seeking personal gain through the “blatant abuse” of a program that allows employees to build up the lump sum over three years but forces them to surrender their jobs afterward. County officials said the program was set up for career county employees and never envisioned as an option for an elected official who could be returned to office, continue earning a salary and, presumably, pile up additional retirement benefits.

“It goes to Stan Barry’s honor and integrity,” Fairfax County Republican Committee Chairman Anthony Bedell said. “Technically, he’s not violating the law. But the point is he found a loophole. Is this who you want for your sheriff? A guy who is walking between the raindrops to game the system?”

In an interview, Barry said Republicans have ginned up a bogus allegation from the complexities of the DROP program to help their candidate for sheriff, Bill Cooper.

“They’re saying explicitly I will fleece the county of a million dollars if I am reelected,” Barry said. “The short answer is that I will not collect one penny if I am reelected.”

Under an arrangement that Barry said has been vetted by the county attorney’s office, Barry would not collect any lump sum until his term is completed. Instead, the benefits would be put aside in a separate account. Those benefits also would not accrue interest, as other employees’ DROP accounts do, he said.

Nor would he receive additional retirement credits for years of service during his term, Barry said. If anything, the arrangement would save the county money, he said.

Barry accused the GOP of exaggerating how much money he would receive even if he were to collect the lump sum, saying the $1 million figure is “totally made up.”

“I have to hand it to them,” Barry said, adding that the GOP has chosen an issue with details that are difficult to explain to voters. But he said that if he wins, he would serve even if he no longer could collect a salary or additional retirement benefits.

Republicans say the issue still raises doubts about Barry’s trustworthiness.

“That’s his version,” Cooper said. “But that’s not how the program was set up. I can tell you that 11,000 other county employees can’t do what he is doing.”

The DROP program, which became effective July 1, 2005, was set up to give employees more flexibility in managing their retirement benefits. Under DROP, an employee who is eligible to retire can choose to continue working for three years. In that time, the employee would continue collecting a salary, while retirement benefits would be placed in a special interest-bearing account.

However, those additional three years in the DROP program would not count as additional years of service and therefore would not boost the employee’s eventual payouts. At the end of the three years, the employee would also be required to leave his post.

Besides giving employees flexibility, the plan was supposed to enhance workplace planning for the county. Managers would have a more definite idea of when an employee would leave and would have more time to train successors.

At its June 7 meeting, the Board of Supervisors deferred action to study the issue further before acting to close the loophole for elected officials.

Last week, the GOP unveiled a “DROP Stan Barry” video, using clips from the June 7 meeting to make the case that Democratic and Republican supervisors were outraged by Barry’s use of a loophole. The GOP also posted documents calculating how much Barry stood to collect on his $161,000 salary. Republicans said the party plans to keep hammering at the issue until Election Day, on Nov. 8.

Supervisor Michael R. Frey (R-Sully) said Friday said that because Barry had enrolled in DROP, he should not have run for reelection. Frey said it’s not fair that other county employees would be required to retire after three years of DROP but that Barry could collect the lump sum and keep working if voters return him to office.

“He made a decision, and he needs to stick with it,” Frey said.