A pair of Republican Congressmen want the Government Accountability Office to investigate delays by the FDA in disciplining researchers who break rules while testing drugs in people, Bloomberg News reports. Joe Barton of Texas and John Shimkus of Illinois wrote a letter to the GAO saying the FDA’s oversight of clinical trials needs to be reviewed “thoroughly.”

Their letter cited a Feb. 29 Bloomberg News report that said the FDA failed to complete disciplinary action against 12 researchers after proposing that they be disqualified from trials based on findings that they violated agency rules to protect patients and ensure accurate data. Cases have remained unresolved for as long as a decade, allowing researchers to work on more studies.

The “FDA has waited months and sometimes years to take action against doctors who lied about their work on critical clinical studies of new drugs and who put their own patients at risk,” Barton said in a statement. “There’s just no excuse for not invoking the authority FDA already has to rapidly disqualify liars from taking any further role in these drug studies.”

Barton is the top Republican on the House Energy and Commerce Committee, which oversees the FDA, and Shimkus is the top Republican on the panel’s Oversight and Investigations Subcommittee.

In addition to investigating delays, they asked the GAO to examine whether the FDA’s oversight is “effective in identifying clinical investigators whose practices or conduct may compromise the quality and integrity of clinical data or the safety of participants in clinical trials.”

The Bloomberg News story described the case of James Vestal, a Texas doctor who the FDA said submitted falsified data from a drug trial and enrolled patients who should have been excluded for safety reasons. Agency investigators wrote a report on Vestal and then the FDA took more three years to begin the disciplinary process, allowing Vestal to work on additional trials.

Vestal’s case remains pending and he has voluntarily agreed not to do any additional studies while his lawyer negotiates with the FDA. Vestal and his Washington lawyer, Philip Katz, have declined to comment.

The FDA recognizes the disciplinary process needs improvement and is developing timelines to regulate how long it takes to punish those who violate its drug-test rules, agency officials have said.