WASHINGTON -- Luggage theft. Drug use. Sleeping on the job. These are just a handful of nearly 10,000 reports of misconduct involving employees at the Transportation Security Administration from 2010 to 2012, according to a new watchdog report.

As disturbing, wrote federal investigators, is that these allegations are on the rise: increasing from 2,691 reports of misconduct in 2010 to 3,408 in 2012. One such case came from Orlando International Airport, in which a TSA baggage screener in 2011 pled guilty to charges of stealing laptop computers and other electronic devices worth an estimated $80,000 from passenger bags.

While roughly a third of the 9,622 cases cited by investigators dealt with attendance issues -- the most common infraction -- many others touched on allegations that could put air travelers at risk as they travel through the roughly 450 airports guarded by TSA employees.

About 2,000 times TSA employees were cited for “screening and security” infractions such as lettings bags through without screening them or “sleeping on duty,” according to the Government Accountability Office, an agency that acts as the investigative arm of Congress.

In one case at an unnamed airport, a screener let bags pass through an X-ray machine “without stopping the conveyor belt to review each image” as required under regulations, according to the report. That employee was suspended for a month. In another case, a TSA employee helped sneak a piece of luggage through security for a family member. When a supervisor subsequently checked the bag, it was found to contain “numerous [unnamed] prohibited items” and the employee was suspended for a week.

Penalties for these infractions ran the gamut, although a letter of reprimand was the common response -- occurring 47 percent of the time. About three in 10 were suspended for violations, and roughly one in five were fired or resigned for their misconduct.

The range in penalties led GAO investigators to conclude that TSA needs a better system in place to ensure that misbehaving employees are penalized properly.

“Specifically, TSA does not have a process to conduct reviews of misconduct cases to verify that TSA staff at airports responsible for adjudicating employee misconduct comply with policies and procedures, nor does the agency record the outcomes of all cases or track the cycle time to complete the investigations and adjudications process,” noted the authors of the GAO report.

At a congressional hearing Wednesday, a top TSA official said the agency already has taken steps to address the concerns by developing a system to standardize the penalties. In addition, TSA Deputy Administrator John Halinski noted in his opening remarks that the agency hoped to counter the danger of an “insider threat” through a new program intended to watchdog TSA employees. 

“While the vast majority of TSA employees are hard-working, professional and abide by the highest ethical standards, a single bad act by one employee can create a security vulnerability,” he said. 

About 56,000 people work at TSA.

A longtime TSA critic -- U.S. Rep. John Mica, R-Winter Park -- jumped on the findings as more evidence that Congress should reconsider the use of private screening companies at airports. 

“The report confirms our worst suspicions that TSA employee misconduct has spun out of control,” Mica said in a statement.  “It is time to reassess TSA’s role in the aviation screening process and return the agency to security and intelligence responsibilities and remove them from the personnel and human resources businesses at which they are failing.”