Updated

Fines are being imposed indiscriminately against airline passengers who have knives and other banned items in their carry-on bags, lawmakers say.

Rep. John Mica (search), R-Fla., chairman of the House aviation subcommittee, said the Transportation Security Administration (search) fines some people for an offense at one airport but lets others go elsewhere for the same infraction.

Rep. Peter DeFazio (search) of Oregon, the ranking Democrat on Mica's subcommittee, said he mistakenly brought his mustache scissors to the airport. TSA screeners allowed him to mail them home.

After checking the TSA's Web site for its guidelines on fines, DeFazio said he didn't understand why he wasn't penalized.

"It says any minor infraction would be a $250 fine, with nothing in the form of a disclaimer," he said. "I thought, `Wow, they didn't fine me $250.' We have an equal application of the law problem."

TSA issued guidelines last month on the range of fines applied to each violation. Travelers caught with knives could be fined $250; passengers with explosives - such as fireworks or blasting caps - could get as much as $10,000.

TSA spokesman Mark Hatfield said the agency tries to avoid fining people for innocent mistakes. He said only about 1,500 people have been fined in the last six months even though the agency has seized more than 3 million prohibited items.

"Your Swiss Army keychain knife isn't going to get you a fine," Hatfield said. "A 4-1/2 inch butterfly knife is."

The guidelines for fines include aggravating factors, such as "attitude" and "artful concealment" that can bring a stiffer fine. Critics say the TSA needs to be more specific about what constitutes "attitude."

Someone caught carrying a dangerous item onto a plane is notified through the mail that they've been fined.

Mica and DeFazio are considering holding an oversight hearing on the issue.