Over loud boos from a dozen protesters outside the Senate chamber, two Republican leaders unveiled legislation Thursday that would crack down on local laws and school policies requiring bathroom accommodations for transgender Texans.

Lt. Gov. Dan Patrick said Senate Bill 6, filed Thursday, would "protect businesses from government interference" by overturning local ordinances that allow transgender people to use the bathroom that conforms with their gender identity. Each business would be free to form its own policies, he said.

The bill also would require public schools and universities, as well as government buildings, to designate bathrooms for use by people "according to their biological sex," said the bill’s author, Sen. Lois Kolkhorst, R-Brenham. Schools would be free to make accommodations, including single-occupancy bathrooms and locker rooms, for transgender students, she said.

"We know it’s going to be a tough fight," Patrick said. "The forces of fear and misinformation will pull out all the stops, both in Texas and nationally, but we know we are on the right side of the issue, we are on the right side of history."

Critics called the bill discriminatory and predicted that if it were to pass, Texas would experience boycotts and backlashes from businesses, sports leagues, entertainers and travelers comparable to what happened to North Carolina when it passed a similar law last year.

"This bill isn’t about providing safety or privacy. It’s an attempt to foment divisiveness, stigmatize vulnerable students and distract us from what really needs our attention — more resources for our schools and educators," said Louis Malfaro, president of the Texas branch of the American Federation of Teachers.

Chuck Smith with Equality Texas called the bill misguided.

"If we’re seriously interested in protecting people and trying to stop predatory behavior, then the target of the legislation should be predators. The target should not be transgender people because transgender people are more likely to be the victims of crime, not the perpetrators," Smith said.

Patrick, who presides over the Senate, said the bill was needed to protect privacy and ensure that sexual predators do not use transgender bathroom laws to enter women’s bathrooms. To that end, SB 6 would create enhanced criminal penalties for crimes committed in public bathrooms, locker rooms or changing facilities, Kolkhorst said.

"The right of every Texan will be protected when they find themselves in the most intimate private setting," she said.

Enforcement would not require "bathroom police," Kolkhorst added.

The bill would allow citizens to file an attorney general complaint if a school or government enforced a prohibited transgender bathroom policy that was not changed within three days. Civil penalties would be $1,000 to $1,500 for a first violation, rising to $10,000 to $10,500 for each additional day of violation.

The bill’s prospects are uncertain in the legislative session that begins Tuesday.

Particularly with Patrick’s strong support, passage can be expected in the Senate, where Republicans outnumber Democrats 20-11 (support from 19 senators is required to have a vote on most bills) and where the GOP caucus has grown far more conservative in recent years.

The House could prove to be a different matter. Speaker Joe Straus, R-San Antonio, has indicated that his priorities lie elsewhere, particularly addressing problems with Child Protective Services, improving mental health and reforming school finance to reduce the property tax burden on so-called property wealthy districts like Austin.

Strong opposition from the Texas Association of Business — joined by such large companies as Apple, IBM and Intel— also undercuts support from a source that Republicans typically rely upon.

The business group released a study last month warning that legislation like the transgender bathroom bill could cost the state economy up to $8.5 billion a year and threaten 185,000 jobs. Passage would bring boycotts affecting the travel and tourism industry, discourage businesses from relocating or expanding in the state and make it difficult to recruit and retain talented workers to Texas, the study said.

Patrick dismissed what he called "predictions of economic doom," saying states with liberal transgender policies are at the bottom of the economic ladder, while states like North Carolina, which has experienced an economic backlash over a law similar to the one proposed for Texas, have robust economies.