A new government audit says the Transportation Security Administration is failing to uniformly discipline airport screeners who break the rules. NBC's Pete Williams reports.

The chairman of a congressional subcommittee on oversight and management efficiency Wednesday called on the Transportation Security Administration to crack down on “the napping, the stealing, the tardiness, and the disrespect” a day after a watchdog’s report revealed a spike in TSA misconduct.

The TSA investigated and closed 9,622 cases of employee misconduct between the years 2010 and 2012, according to a report released Tuesday by the Government Accountability Office.

The figure marked a 26 percent increase in misconduct cases in a three-year period.

Thirty-two percent of the cases involved problems with workers showing up for their jobs, according to the report, and 20 percent had to do with security and screening.

The report was released ahead of a hearing before the House Homeland Security Committee on Wednesday morning that included representatives from the TSA and GAO.

In one case mentioned in the GAO report, an employee left an assigned checkpoint to help a family member get a bag -- later found to contain "numerous prohibited items" -- past screening. The employee was suspended for seven days, according to the report.

In another case from January 2012, two former employees of the TSA were sentenced to six months in jail after they admitted to have stolen $40,000 from a bag at John F. Kennedy Airport, NBC New York reported.

Of the more than 9,000 misconduct cases closed by the TSA over the three-year period, nearly half resulted in a letter of reprimand, while employees were suspended in 31 percent of cases, according to the report. Only 17 percent of the employees found to have engaged in misconduct were removed from their jobs.

Rep. Jeff Duncan, R-S.C., the chairman of the subcommittee on oversight and management efficiency, said on Wednesday that a few bad employees contributed to a poor public perception for the agency.

At a House hearing on TSA integrity and misconduct by airport security personnel, Chairman Jeff Duncan, R-S.C., called upon them to "stop with the napping, the stealing, the tardiness, and the disrespect. Earn Americans' trust and confidence."

“While I know that there are many thousands of hardworking, dedicated employees working at airports throughout the country, and it’s unfair to generalize to the whole workforce, unfortunately a few bad apples can ruin the bunch,” Duncan said. “These findings are especially hard to stomach since so many Americans todays are sick of being groped, interrogated, and treated like criminals when passing through checkpoints.”

“If integrity is truly a core value, then, TSA, it’s time to prove it. Stop with the napping, the stealing, the tardiness, and the disrespect, and earn America’s trust and confidence,” Duncan said.

TSA Deputy Administrator John Halinski said that in cases where it can be immediately proved that an employee committed a form of misconduct, “I’m going to walk him out the door.” Most cases of alleged wrongdoing require an investigation, he said.

The agency is nearly 12 years old, and has 55,000 employees and a budget of more than $7.5 billion.

The need for strict guidelines on how to discipline employee infractions had led to inconsistencies, said Rep. Bennie Thompson, D-Miss.

“The bulk of employee misconduct cases are handled at the airport level, meaning that what happens at one airport may differ from what happens at another,” Thompson said in an opening statement.

The variety of workplaces involved “underscores the need to have clearly defined and consistently applied procedures” regarding employee discipline, Stephen Lord, GAO director of forensic audits and investigative services, said at the hearing on Wednesday.

The GAO report included four recommendations for executive action, all of which have been endorsed by the TSA, Lord said on Wednesday. The recommendations include developing guidelines to record and report misconduct for TSA officials at all airports and establish a review process for all allegations of misbehavior.

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