While legislation proposed this week would bar members of Congress from flying first class at taxpayers' expense, Capitol Hill lawmakers have another travel perk not likely to disappear anytime soon: free parking at Washington-area airports.

All 435 House members and 100 senators are allowed to use "restricted" parking areas at Ronald Reagan Washington National and Washington Dulles International airports. The special lots not only are free to lawmakers but also are closer to the airports' terminals than other parking areas.

The courtesy also is extended to the nine Supreme Court justices and foreign diplomats. Each congressional office, justice and embassy receives two passes for the restricted parking areas at the two airports.

That's not to say everyone with the privilege will find an open space when they show up at the airport. Only 100 out of Dulles' 24,000 overall parking places are reserved for those with the special passes, while National's restricted parking area fits 89 vehicles, compared with almost 8,900 overall parking spaces.

Still, if those with access find the special lots full, they can use any public parking area at the airport for free.

The privilege, which has existed for many years, is extended partly because both airports are owned by the federal government, said a spokeswoman for the Metropolitan Washington Airports Authority, which manages the airports.

Baltimore/Washington International Thurgood Marshall Airport also offers limited courtesy parking to members of Congress, but a spokesman couldn't provide details.

Not all those with access to the restricted parking lots routinely take advantage of the privilege, as Supreme Court justices, some senior Capitol Hill lawmakers and foreign ambassadors often use drivers to drop them off at the airport.

Once they're inside the airport, rank-and-file members of Congress aren't exempt from the much-maligned airport security screening, though they're eligible -- like most Americans -- to apply for the Transportation Security Administration's fast-track screening program.

Unlike most Americans, however, lawmakers don't have to pay the $85 application fee for TSA's Pre-check program.

A small handful of high-ranking congressional leaders who routinely travel with police or security details can bypass normal TSA security checkpoints, though their offices declined to offer details, citing security reasons.

Members currently can fly first class on commercial airlines at taxpayers' expense, though many choose to sit in coach to stretch their offices' travel budgets.

It's not clear how many Capitol Hill lawmakers fly first class, as they don't have to disclose the distinction on their expense reports. But the option soon could vanish, as a bipartisan group of House members introduced legislation Monday that would prohibit lawmakers from using taxpayer money to fly first class on commercial airlines.

The "If Our Military Has to Fly Coach Then So Should Congress Act" seeks to extend to the legislative branch the same restrictions on first-class air traveled placed on many government employees.

"As representatives of the American people, we in Congress have a responsibility to wisely use the people's money," said Rep. Walter Jones, R-N.C., one of the bill's initial four co-sponsors. "Members of the House and Senate should never secure their own luxury travel at taxpayer expense, but they especially should not do so when our nation is buried $17 trillion deep in debt."