Residents hoping to hold Missouri government unions accountable for members doing union work on the taxpayer dime—a practice known as "release time"—have little recourse because of loopholes in public records laws, according to a new report.

The Competitive Enterprise Institute, a think tank based in Washington, D.C., filed public records requests across the Show-Me State regarding union release time only to come up empty. Most school systems did not monitor or disclose union activity that happens during regular business hours.

"Many Missouri government employers did not track release time records and could not provide the cost, amount or activity performed on release time," the report says.

Trey Kovacs, CEI labor expert and author of the report, also found that many school districts refused to cooperate with his inquiries.

Some officials claimed that the union activities were exempt from transparency laws. Officials from the Kansas City, Mo., school district, one of the largest in the state, declined to fulfill the request after its lawyers ruled that records "related to a specific employee activity are closed under the Open Records Act."

"Another impediment is that some government officials determined that release time records are closed by law, even while others considered release time records open to the public," the report says.

The Missouri Department of Education did not return a request for comment.

Some school districts were able to provide records of their union release time. Some of that leave was used "conducting partisan political activity or attending union meetings and conferences," including lobbying days at the state capitol. CEI found that taxpayers were paying thousands of dollars in subsidies for union business.

"During the 2011-2012 school year, the Parkway School District issued the Communication Workers of America (CWA) 20 days of release time at a cost of $2,489.76. Additionally, the school district paid $25,602 of the Parkway National Education Association (PNEA) president’s $87,300.00 salary," the report says.

Many public sector agencies allow employees who work full time as union representatives to remain on the public payroll even if they give up their government duties. A 2014 Washington Examiner investigation revealed that more than 700 federal workers spent at least half of their work days doing union business and that taxpayers paid union officials $155 million between 1978 and 2011.

Groups in other states are challenging this system, saying that taxpayers should not subsidize union activities.

The Fairness Center, a nonprofit watchdog group in Pennsylvania, filed a lawsuit against the Philadelphia Federation of Teachers and the School District of Philadelphia in February, in the hopes of ending the practice. Philadelphia’s contract with the teachers union allows up to 63 teachers to transition into full-time union roles, which could cost taxpayers as much as $4 million, according to the suit.

David Osborne, general counsel for the Fairness Center, said that Philadelphia also lacked transparency to monitor union activity. Aside from the clause governing union release time in the union’s contract, the school district kept few records of union business.

"It was disturbing to discover that the School District of Philadelphia has no oversight of these teachers once they are selected by the union," Osborne said in a February interview with the Washington Free Beacon. "The district could provide zero records on how the PFT is employing these ghost teachers. The collective bargaining agreement even allows [union president] Jerry Jordan to dictate to the district the salaries of the teachers he selects."

Other groups have successfully eliminated the practice of union release time. The city of Phoenix ended the practice in 2014 after a successful legal challenge by the Goldwater Institute.

CEI said that properly tracking union release time should be an obligation for any taxpayer-funded agency, in order to provide transparency to taxpayers.

"The hours and cost of release time in Missouri obtained by CEI’s survey is just the tip of the iceberg," the report says. "Government unions are the primary beneficiaries of release time and they use it to promote their own ends, not a public purpose. Only government unions benefit from lobbying legislators, attending union conferences, or any other activity performed on release time."