Montana has never been known as a black-tie place. Governors wear cowboy boots and bolo ties, and people joke that a tuxedo is a pair of black jeans and a sport coat. But this winter, when lawmakers arrive at the state Capitol, they will have to abide by a new dress code: No more jeans. No casual Fridays. And female lawmakers "should be sensitive to skirt lengths and necklines."

Republican leaders who approved the guidelines say they are simply trying to bring a businesslike formality to a state Legislature of ranchers, farmers and business owners that meets for only four months every other year. But the dress code has set off a torrent of online mockery, and is being pilloried by Democratic women as a sexist anachronism straight from the days of buggies and spittoons.

"The sergeant-at-arms could be standing there with a ruler, measuring hemlines and cleavage," said Jenny Eck, a Democratic House member from Helena.

Eck said she was leaving a health care forum in Helena, the capital, on Monday when one of her Republican colleagues peered at her and told her that he was glad to see she was dressed appropriately.

"It just creates this ability to scrutinize women," Eck said. "It makes it acceptable for someone who’s supposed to be my peer and my equal to look me up and down and comment on what I’m wearing. That doesn’t feel right."

About a third of the state legislatures in the country had written rules for how lawmakers, staff members and visitors were supposed to dress when they were on the statehouse floor, according to a 2006 survey by the National Conference of State Legislatures, the most recent nationwide look at the issue. Others had unwritten codes for what not to wear.

Most simply called for business attire, but some were quite particular, according to the survey. New Jersey asked state senators to wear suits, not sport coats. Pennsylvania let House members take off their jackets on the floor, but they had to put them on again to speak. Women in Ohio could not wear sleeveless shirts, but short sleeves were fine. In Georgia, suit coats for men and "dignified dress" for women were expected.

Things do ease up at the week’s end. Oregon lets Senate pages wear navy polos on Fridays, and lawmakers in Hawaii are allowed to wear aloha shirts on Aloha Fridays.

Montana’s one-page list of fashion guidelines (officials say they are not formal rules) were handed down Dec. 5 in what Rep. Keith Regier, the House Republican majority leader, said was a response to questions from newly elected lawmakers about what to wear on the floor.

"We do hold decorum at a high standard," Regier said. "What we’re saying is: Be appropriate in what you wear. Don’t wear something that could be a distraction from the legislative process."

The seven-point list covers men’s attire, calling for a suit or a jacket and tie, dress slacks and shirt, and "dress shoes or dress boots." But the guidelines for women are a little longer and more detailed, and had many female lawmakers rolling their eyes. The list includes what kinds of footwear they should avoid (flip-flops, tennis shoes and open-toe sandals), declares that leggings are not dress pants, and encourages modesty on skirt lengths and necklines.

"It’s like something out of ‘Mad Men,’" said Rep. Ellie Hill, a Democrat from Missoula, referring to a television drama set in the 1960s. "The whole thing is totally sexist and bizarre and unnecessary."

But Lindsey Grovom, the chief clerk who worked with House leaders to develop the new attire guidelines, said she had been taken aback by the uproar. She said there was nothing sexist about asking for professional attire from elected representatives. In fact, before this blew up, she said, her biggest concern had been the decision to scrap Montana’s tradition of allowing jeans during Saturday morning sessions.

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