Taxpayer-funded union activity is drawing new scrutiny after the Obama administration carved out a furlough exemption for government workers who serve as labor representatives.

The Office of Personnel Management, the agency managing federal employee issues, last Friday opened the door for some workers who serve as union representatives across the federal government to return to work and receive regular paychecks while most of their colleagues remain furloughed.

After complaints from government workers that they lacked union representation during the shutdown, OPM last Friday rewrote its previous guidance to allow those employees who are involved in representing co-workers on union-related matters to return to work with a regular paycheck.

The Washington Examiner first wrote about the change on Saturday.

Conservative groups deeply opposed to taxpayer-funded union activity accused administration lawyers of sneaking in a way to lift the furlough for some of Obama's biggest supporters — government workers who also serve as union representatives.

In 2011, the government spent $156 million on employees who devote at least some of their time to serving as union stewards working for outside labor groups on behalf of their co-workers, according to OPM.

The practice, known as “official time,” is difficult to track because OPM only includes the total amount of dollars spent on the union activity not how many government employees at each department are being paid to do union work.

The Washington Examiner's Mark Flatten conducted an extensive investigation of the matter. Using Freedom of Information Act requests to government agencies, he is completing a database tracking how many employees are engaged in union work at each government department and agency. So far, he has tracked down more than a thousand.

The research also shows that some of these union representatives are commanding six-figure salaries — all paid for by taxpayers.

At least 19 union workers in the Department of Veterans Affairs were paid more than $100,000 each in 2011, not including benefits.

The Social Security Administration has six workers who spend all of their time on union work and who make more than $100,000. Three of them who were hired by SSA to serve as administrative law judges make $164,000 or more.

“We were stunned to learn how much the average union representative is being paid by the U.S. taxpayer,” said Nathan Mehrens, president of Americans for Limited Government, a group opposed to taxpayer-funded union activity.

"It is absurd that even as the federal government continues to roll up more than $700 billion in debt each year, that public employee union representatives are being paid more than $150 million a year in taxpayer dollars," he added.

Neither OPM nor the American Federation of Government Employees, the top federal-worker union, has responded to inquiries on why the exemption for union representatives was made.

Trish Gilbert, executive vice president of the National Air Traffic Controllers Association, said her union is still trying to get answers from OPM on whether labor representatives who were furloughed can return to their offices to do union work.

About 5,000 agency safety inspectors, airline-oversight staff and traffic-control support personnel were furloughed as a result of the shutdown, although 800 of those were sent back to work on Tuesday.

Gilbert pointed to the example of union involvement during drug testing of air-traffic controllers and other safety staff. Federal law requires union representatives to be available during random drug testing of employees, she said.

The union representatives are there to ensure that drug-testing machines are calibrated properly and samples are properly identified and safeguarded.

The first week of the shutdown, before the new OPM guidance was issued, employees were denied a union representative during random drug tests, Gilbert said.

“When air traffic employees are pulled into drug and alcohol testing, by law, they must have time to confer with union representatives,” she said. “They are there to ensure that the process is properly followed.”

Rep. Phil Gingrey, R-Ga., who wrote a bill that would prohibit taxpayer funding for labor activities and has pressed departments for more information about the practice, said the furlough carve-out for union representatives is unfair both to other federal workers and taxpayers.

After OPM's change, union representatives at the Social Security Administration can do union work for pay during the shutdown while other workers are being barred from processing new claims — a situation Gingrey says is unfair to seniors.

“The SSA's practice of allowing union activity during normal federal government operations is unfair to seniors and taxpayers,” he said. “Rewriting shutdown guidelines to allow union bureaucrats to continue this practice is reprehensible.”

The Obama administration's decision to allow union representatives to return to work during the shutdown even has some Democrats scratching their heads.

Five House Democrats interviewed by the Washington Examiner on Thursday said they didn't know enough about the issue to comment.

But one liberal Democrat said the Obama administration's exemption for union representatives is the same type of “picking and choosing” Democrats have accused House Republicans of engaging in when they pass bills to fund certain government agencies, such as the Department of Veterans Affairs. The Senate has blocked those piecemeal efforts to reopen select parts of the government.

“I don't think any workers should be off the job, period,” Rep. Jim McDermott, D-Wash., told the Washington Examiner. “But picking and choosing is inherently unfair because there's no basis for that.

“You're union, therefore you get a paycheck and you're not union and you don't? C'mon, everybody has bills to pay, they have children to feed, they have daycare to pay for and medicine,” he added.

Rep. Collin Peterson, a conservative Democrat from Minnesota who serves as the Agriculture Committee’s ranking member, said the furlough exemption is just one of many odd carve-outs both Congress and the administration has implemented during the shutdown.

“A lot of what they're doing doesn't make a lot of sense,” he said.

“We voted on Saturday to make sure people who are furloughed are paid. That doesn't make a lot of sense either,” Peterson added. “Why would you lay somebody off and then pay them. What are people thinking? This whole place has gone crazy.”