A young, female reporter recently tried to enter a guarded room known as the Speaker's lobby outside the House chamber, but her outfit was considered inappropriate because her shoulders weren't covered. She was wearing a sleeveless dress.

Forced to improvise, she ripped out pages from her notebook and stuffed them into her dress's shoulder openings to create sleeves, witnesses said. An officer who's tasked with enforcing rules in the Speaker's lobby said her creative concoction still was not acceptable.

The Speaker's lobby, a room adjacent to the front of the House chamber, is a go-to location for reporters wanting to grab lawmakers for brief interviews, and there are allegedly rules about what you can wear inside. Even as denizens of Capitol Hill wipe away sweat from Washington, D.C.'s swamp-like weather outside, men are expected to wear suit jackets and ties in the House chamber and Speaker's lobby. Women, on the other hand, have been told they're not allowed to wear sleeveless blouses or dresses, sneakers or open-toed shoes.

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These rules are far from clear cut and there are no visible signs defining them. They are also not enforced on the Senate side of the Capitol.

Some lawmakers have loosely interpreted these rules, which prompted Speaker Paul Ryan, R-Wisconsin, to recently reiterate an announcement made to House lawmakers over the years: "Members should periodically rededicate themselves to the core principles of proper parliamentary practice that are so essential to maintaining order and deliberacy here in the House."

Among them: "Members should wear appropriate business attire during all sittings of the House however brief their appearance on the floor may be."

That directive also extends to the Speaker's lobby, where reporters, armed with their voice recorders, position themselves as they wait for members to exit the floor in order to snag an interview. The dress code is only enforced inside the Speaker's lobby -- not along the rest of the chamber's perimeter.

On the day the House voted in early May to pass the Republican health care bill, Haley Byrd, a congressional reporter for Independent Journal Review (IJR), said she was kicked out of the Speaker's lobby because she was wearing a sleeveless dress.

"When I was kicked out that day, I was just trying to pass through the area to reach another hallway, but I was told I was violating the rules. They offered to find a sweater for me to put on, so it wasn't some tyrannical end of free press, but I opted to just go around instead. But recently they've been cracking down on the code, like with open-toed shoes," she said, adding that sometimes she walks fast and those on patrol don't notice.

"I suspect the rules are being emphasized now that it's summertime and excruciatingly hot outside and everyone is dressing for the weather."

Men have been offered what one former reporter, Jacob Fischler, has dubbed "ties of shame," exhibited below, if they left theirs at home.

Frankly, I look good. RT @KateNocera @ItsFischy in the Tie of Shame™ for ppl who forget to wear ties to Capitol Hill. pic.twitter.com/Gi2QFlEE2M — Jacob Fischler (@ItsFischy) October 10, 2013

"All House Floor rules made for Members of Congress and their staff apply to the Speaker's Lobby," Ryan's spokeswoman, AshLee Strong, told CBS when asked about the rules.

Strong also noted after the publication of this story that this dress code existed under previous House speakers, too, including Nancy Pelosi, a Democrat.

A senior GOP source told CBS News that House chamber security and the House Sergeant at Arms enforce rules regarding proper business attire in the Speaker's lobby. Leadership floor staff, with help from the Sergeant at Arms, enforce the rules on the House floor.

There have been exceptions to these so-called rules, of course. Former first lady Michelle Obama wore sleeveless dresses to several State of the Union addresses inside the House chamber. President Trump's daughter, Ivanka, was spotted in the House gallery during her father's joint address to Congress in February wearing a slightly off-the-shoulder dress with what appeared to be her bra strap showing.

Some lawmakers have also been seen violating the rules. Rep. Bobby Rush, D-Illinois, was escorted from the floor in 2012 for wearing a hoodie to protest the shooting of Trayvon Martin.

Billy House, congressional correspondent for Bloomberg News, is chairman of the Standing Committee of Congressional Correspondents. The notion of a dress code for reporters or anyone else in the Speaker's lobby, he said, stems from the idea of "proper decorum," which is a phrase typically included in the rules package at the start of each Congress, but it's not elaborated on.

"However, for anyone hoping to find any actual, official code of attire? Good luck," he told CBS News.

If there ever were specific articles of clothing outlawed on paper, those documents seem to have disappeared.

"Original congressional source material that might add more specificity has either been thrown away with someone's old knee breeches, or powdered wigs, or hidden away, or never actually written down and distributed," he added.

The only specifics that exist -- and they're not extensive -- lie in Jefferson's Manual and Rules of the House of Representatives, which spells out the history of the somewhat vague guidelines. In the 96th Congress, then-Speaker Tip O'Neill, a Democrat, "announced that he considered as proper the customary and traditional attire for Members, including a coat and tie for male Members and appropriate attire for female Members," a 2015 edition of the manual said. It added that the House then adopted a resolution that required Members "to wear proper attire as determined by the Speaker."

But even though the rules surrounding proper attire have not been modernized at the same rate as fashion, they evolved once before. The manual, for example, notes that lawmakers originally wore hats in session, as they did in Britain's Parliament, but that custom was "abolished" in 1837.

Fashion rules in British Parliament actually seem to be evolving faster than in the House of Representatives. The speaker of the House of Commons, John Bercow, broke with tradition and announced last week that male lawmakers no longer need to wear ties in their chamber, according to British media, and that they should just focus on wearing "businesslike attire."

As far as the House rules, Billy House noted that the enforcement of a ban on sleeveless dresses, tennis shoes and open-toed shoes has been subject to the discretion of chamber security. He said that the Standing Committee of Correspondents expects that those seemingly unwritten rules should be enforced in an even fashion.

"The committee expects enforcement to be geared and directed not just to reporters in the Speaker's Lobby -- but lawmakers and congressional staffers, as well," he said.