Rep. Barney Frank on the House floor on Monday. (C-SPAN)

The sight of Rep. Barney Frank wearing a casual t-shirt on the House floor Monday caused more than a few raised eyebrows — room temperature notwithstanding.

Hillary Clinton showing a bit of clavicle in the Senate in 2007. (Courtesy of C-SPAN)

Now, now, kids: It should be known that Frank recently had surgery on his left hand and is wearing a cast and sling these days, which makes it difficult to put on a dress shirt and tie. We’re told he dropped by the office Monday with no plans to appear in public, but was asked to manage a bill because no other member was available. Frank borrowed a jacket from a staffer, according to his spokesman, draped it because it didn’t fit over the cast, and headed to the House floor.

Frederica Wilson wearing one of her trademark hats. (Alan Diaz/The Associated Press)

The rules are vague but rigorously enforced: Coat and tie for men, “appropriate attire” for women. Jack Kennedy reportedly caused a scandal by wearing golf shoes onto the Senate floor. Then-Rep. Pat Schroeder supposedly broke tradition as the first woman to wear pants on the House floor in the 1970’s — though some accounts say it was Susan Molinari or Cynthia McKinney. (Update, 12/21: Rep. Charlotte Reid was the first in pants)

Hill veterans say Sen. Robert Byrd used to lecture female senators about open-toed shoes; John Ensign, who frequently jogged on the mall, would run in and borrow a jacket in order to cast his vote.

Sleeveless dress were once forbidden, but that was before Michelle Obama displayed her bare arms in the House chamber. The random turtleneck has been tolerated, but the no-hat provision has been enforced for more than 150 years. Bella Abzug couldn’t change it; freshman Rep. Frederica Wilsonknown for her signature toppers back in Florida — fully expected that Speaker John Boehner would overturn the ban. But eleven months later, she told us she’s “still wishing and hoping.”

And yet — Jim Traficant’s toupee was perfectly acceptable. Go figure.

Read also: Hillary Clinton’s tentative dip into new neckline territory, 7/20/2007

Hats off for Florida congresswoman-elect Frederica Wilson, 12/2/2010.

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