Sen. Jim DeMint, R-S.C., thought he had plugged a big gap in the nation's port security system last month when the Senate unanimously adopted his measure to bar felons from working in sensitive areas of the nation's seaports. But as The Wall Street Journal recently reported, his measure was dropped from the Port Security Act when it went to conference with the House. That means persons convicted of serious crimes may be able to qualify for a new biometric government security card that will be required for workers in sensitive transportation jobs. And that means a dangerous hole in port security remains potentially wide open.

Unfortunately, the threat identified by Sen. DeMint is all too real. The FBI's top counter-terrorism expert recently told The Associated Press he worries the that al-Qaida could make deals with the mafia to smuggle money, people and even weapons into the United States.

When the Department of Homeland Security recently investigated the security of New York and New Jersey ports, they found that nearly half of 9,000 truckers they checked had criminal records According to the Journal, DHS concluded that these workers had "vulnerabilities" that "could be capitalized by terrorist organizations."

The Safe Ports Act bars persons convicted of espionage, sedition, treason, and terrorism from working in sensitive port areas. The DeMint measure would have added a permanent ban for six other felonies, including disruption of transportation, murder and violations of the Racketeer Influenced and Corrupt Organizations Act. It would also have placed an interim ban on access for persons with a recent record of conviction for a range of other serious felonies.

"Felons, through their previous criminal activity, are more likely to be persuaded to look the other way when a suspect shipment comes through the port," Sen. DeMint told the Senate last month. "Someone who will commit extortion, fraud, or traffic in drugs should not be trusted to protect the security of our maritime cargo. While felons do need a second chance, it should not come at the expense of an extremely vulnerable part of the U.S. port infrastructure."

Unions have often protested efforts to bar former prison inmates from transportation jobs, saying that to do so would be unfair. In a statement on his web site, Sen. DeMint blamed Democrats who yielded to "pressure from labor unions" for the conference committee decision, but named no names.

The next move is up to the Department of Homeland Security. A DHS official told the Journal that regulations the department is developing may ban felons from eligibility for the new transportation worker's identity card. But, he said, "It's important that the restriction on felon hiring be codified into law" so that it cannot be overturned by administrative or judicial action. Congress should pass the DeMint measure when it returns.