As any frequent flyer can probably tell you, TSA checkpoints are largely security theater. They’re staffed with blue-shirted government employees that poke through your bags and, if you’re very unlucky, poke through you as well. In fact, they seem to be designed solely to make you miss your flight.

But actually they’re designed to stop bad people from getting onto airplanes. Unfortunately, as lots and lots of evidence has shown, the TSA needs to get lucky to actually stop anyone. That’s backed up by a new report from the Department of Homeland Security’s Inspector General — its internal department watchdog, more or less — details of which were shared (PDF) with the US House Committee on Oversight and Government by IG John Roth.

Basically none of it was good. The IG sent auditors, who were not trained in counterintelligence or how to evade the TSA’s checks, to a number of different airports across the country. The systematic failures in TSA security checks were consistent across every airport, with auditors seeing 95 percent success rates smuggling bombs and guns into secure areas of airports. From IG Roth’s prepared statement to the Committee:

Our testing was designed to test checkpoint operations in real world conditions. It was not designed to test specific, discrete segments of checkpoint operations, but rather the system as a whole. The failures included failures in the technology, failures in TSA procedures, and human error. We found layers of security simply missing. It would be misleading to minimize the rigor of our testing, or to imply that our testing was not an accurate reflection of the effectiveness of the totality of aviation security.

The report goes on to note that simple intelligence and identifying threats for a no-fly list is not enough. A number of recent successful and unsuccessful terrorist attacks were committed by individuals that the intelligence community failed to identify as threats, including Tamerlan Tsarnaev, the mastermind of the Boston Marathon bombings.

"Expensive and ineffective."

It criticizes the TSA’s rules for granting access to the pre-check expedited screening lanes, noting one convicted felon who was a member of a domestic terrorist group was granted expedited screening. The Screening Passengers by Observation Techniques program, which includes some 2,800 TSA employees and $878 million in funding from 2007 to 2012, is "expensive and ineffective," according to the IG’s statement.

The IG found that the TSA does not have adequate monitoring of airport operators to determine if they have properly performed background checks on job applicants, and that criminal histories are rarely documented electronically. That means the TSA is unable to determine with certainty if criminals are gaining access to secured areas of airports.

All is not lost, however. The IG says that his office is "encouraged by TSA’s steps towards compliance with our recent recommendations."