An analysis by a pro-free-market think tank estimates that at least 1,000 federal workers paid with taxpayer dollars exclusively worked for labor organizations rather than performing duties at their government jobs.

Taxpayers spent $162.5 million on federal employees performing union activities in 2014, according to the Office of Personnel Management's most recent data. The Competitive Enterprise Institute used official budget documents and Freedom of Information Act requests to validate how many federal employees worked under such conditions.

"It is likely that thousands of federal employees spend 100 percent of their time performing union activity instead of the public service they were hired to do," the CEI report published Tuesday says (emphasis in the original).

Federal officials have been allowed to perform union work while on the clock since Congress passed the Civil Service Reform Act of 1978. The provision was devised to help workers file workplace grievances and negotiate with their employers, but CEI labor expert Trey Kovacs said the exact nature of the work is unclear thanks to lax accountability measures.

"A general lack of transparency surrounding the practice makes it impossible to know what specific activities are performed on official time or what its costs are," the think tank said. "Despite numerous investigations, federal agencies have done very little to safeguard public funds by properly tracking and reporting on the cost of official time and the number of hours used."

Rep. Jody Hice (R., Ga.) introduced the Official Time Reform Act in March, almost four decades after Congress began allowing taxpayers to foot the bill for union activities. The legislation would prevent federal employees who spend 80 percent of the workday performing union activities from receiving taxpayer-funded bonuses or using their labor work to vest in the federal pension system.

Hice said in a statement that taxpayers should not be forced to foot the bill for representational activities since union representatives were hired to serve the public, rather than their own interests.

"I've questioned many agency heads about their management of official time, and each time, the wasteful pattern emerges and is left unchecked," Hice said in the statement. "Paying federal employees to do union work interferes with providing the services that taxpayers deserve. In order to combat this waste of taxpayer money, the Official Time Reform Act is a much-needed action to overhauling this egregious practice as we seek greater accountability and transparency within our federal government."

Hice pointed to the Department of Veterans Affairs to highlight the wastefulness of the policy in a March press release. The department paid salaries to 300 workers who worked exclusively for public sector unions, just a year after the agency became embroiled in controversy for keeping secret wait lists of veterans for medical appointments. Some veterans on the wait lists died while waiting for care.

The union workers included "nurses, therapists, pharmacists, a physician, and even a prosthetic limb specialist," according to Hice.

"Rather than helping our heroes, these individuals spend all their time engaging in union activities such as collective bargaining, filing complaints or grievances, and even grassroots lobbying," Hice said. "This is unacceptable and a grave misuse of valuable resources."

The nonpartisan Government Accountability Office released a report in February that found the VA spent about $47 million on official time in 2012, though the agency could not "accurately track the amount of work time employees spend on union representational activities."

The House Oversight and Reform Committee voted 23-17 to advance the Official Time Reform Act to the House floor on March 10. A vote on the bill is not scheduled.