AUSTIN — The Senate has passed a bathroom bill that would limit restroom use by transgender men, women and children in Texas.

Senate Bill 3 was approved 21-10 with all Republicans and one Democrat, Brownsville Sen. Eddie Lucio Jr., voting in favor. The bill now heads to the House, where it is expected to have a much tougher time passing.

The legislation would require public school students to use the multi-use restrooms that match the sex on their birth certificates or state-issued identification cards. It would also strike down parts of city laws that protect the right of transgender people to use the restrooms that match their gender identity.

Gov. Greg Abbott added the issue to his list of priorities for this summer special session, which kicked off last week, along with 19 other items such as teacher pay, taxes and abortion.

Just before the bill passed, its author, Lois Kolkhorst, thanked the Senate and its leader, Lt. Gov. Dan Patrick, one of the most vocal supporters of the measure.

"There are many voices on this issue, and y'all know I've always come at this from a women's right issue," the Brenham Republican said. "I'm just one small voice, standing here."

Senators discussed the bill for more than eight hours Tuesday. After giving it preliminary approval around 6:45 p.m., the Senate voted 21-10 to give the legislation final passage just after midnight. Democrats delayed debate for almost two hours but were unsuccessful in using parliamentary procedure to kill it.

During debate, senators repeatedly traded barbs and accusations. The discussion got particularly heated when Houston Democrat Sylvia Garcia asked whether Kolkhorst believes that transgender boys are boys.

"I do know there are differences, and much of that is about science and testosterone," Kolkhorst said. "Scientifically, there's a lot to debate."

When pressed on whether she agreed that transgender boys are boys, Kolkhorst responded, "That's not relevant to this particular bill."

"This bill will harm children," Garcia told Kolkhorst. "Not just to transgender children but to their entire circle of friends, to the whole school and the whole community."

1 / 6State Sen. Lois Kolkhorst, R-Brenham, spoke to Sen. Borris Miles, D-Houston, , during debate on the bathroom bill. (Eric Gay / The Associated Press) 2 / 6State Sen. Borris Miles, D-Houston, speaks during debate over a "bathroom bill" in the Senate Chamber, Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP) 3 / 6State Sen. Paul Bettencourt, R-Houston, speaks during debate over a "bathroom bill" in the Senate Chamber, Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP) 4 / 6Texas Lt. Gov. Dan Patrick, right, listen to Sen. Borris Miles, D-Houston, during debate over a "bathroom bill" in the Senate Chamber, Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP) 5 / 6State Sen. Kirk Watson, D-Austin, speaks during debate over a "bathroom bill" in the Senate Chamber, Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP) 6 / 6Senator Kirk Watson, top left, debates SB3, known as the bathroom bill, in the Senate at the Capitol on Tuesday, July 25, 2017. DEBORAH CANNON / AMERICAN-STATESMAN(Deborah Cannon)

Under Kolkhorst's bill, there would be no penalties for individuals who violate the law, so transgender Texans could not be arrested for simply using the restroom that matches their gender identity. The bill also would not increase penalties for crimes committed in restrooms, showers or changing rooms. Nor would it make it illegal to arrest a man who is not transgender for simply entering one of these intimate spaces.

It would allow Attorney General Ken Paxton to sue political subdivisions, including cities and public school districts, that enact policies allowing transgender people to use the restrooms that match their gender identity but not their personal documents.

Several amendments were adopted Tuesday, the most significant of which would allow Texans to use facilities that match the sex on their state-issued identification card. Transgender children, many of whom cannot change their birth certificates or don't have driver's licenses, would be barred from school bathrooms that don't match these documents.

The bill was also amended to exempt privately leased government buildings, such as stadiums and convention centers. Custodians, parents of young children, emergency responders and caretakers of people with disabilities would be allowed to enter opposite-sex facilities under the bill.

Despite these changes, Democrats echoed the concerns of the transgender community that the bill would worsen the stigma that transgender Texans suffer.

"The text exposes the ugly nature and intent of the bill," said Sen. Kirk Watson, D-Austin. "It is staggering to me, it is shocking, and, I believe, it is shameful that in 2017 a bill in the Texas Legislature was filed, taken to the committee, passed out of the committee, that contained language that expressly allowed discrimination against a group of people.

"Is it any wonder that many, many people believe this bill is meant to discriminate? They took the Legislature at its word," he added.

"Transgender Texans are entitled to the same freedoms as everyone else. Senate Bill 3 will not allow them to enjoy those freedoms."

Kolkhorst repeatedly denied that her bill was meant to discriminate against transgender Texans.

"I know this has been talked about as an anti-transgender-person legislation," she said. "That's not what it's about. It is about the privacy and protection of our small children and our young girls."

Kolkhorst declined to accept two amendments that would have exempted transgender people from the bill's bathroom mandates.

Opposition to the bill has been widespread — with school districts, chambers of commerce and businesses expressing disapproval — but has fallen on deaf ears in the Republican-dominated Senate. On Tuesday, police from several cities, including Dallas, gathered on the Capitol steps to express their disapproval of the bill, which they called a "solution looking for a problem."

Outcries from transgender Texans, their families and friends have been particularly anguished, as they call for recognition and protection from discrimination. During debate last week, more than 250 people showed up to speak against the legislation. The bill passed 8-1 in committee last week after nearly 11 hours of debate.

On Tuesday, several transgender Texans watched the debate from the Senate gallery. Twice, protesters unfurled banners that proclaimed, "Y'all means all." Shouting statements such as, "This is a farce" and "Shame on you," the protesters were escorted out of the gallery without further incident.

Protesters unfurl banners in Senate against bathroom bill, yell "shame" before being escorted out. #txlege pic.twitter.com/6oIqah1PHJ — Lauren McGaughy (@lmcgaughy) July 25, 2017

Democratic Sen. John Whitmire of Houston, the state's longest-serving senator, asked Kolkhorst which bathrooms transgender people should use. Should a trans man with a beard be asked to use the ladies' room, or a trans woman in a dress head toward the men's room?

"Do you understand that the transgender community is not going anywhere?" Whitmire asked her. Mentioning Houston Municipal Judge Phyllis Frye, a transgender woman, he added, "How in the world under your proposed legislation, would she go into a men's restroom?"

Kolkhorst replied that if Frye had her birth certificate changed, she would not be subject to the bill's mandates. Asked about other transgender people who haven't changed their documents, Kolkhorst responded, "I suspect that they would do whatever is necessary for themselves."

Two bathroom bills have been filed in the House, but it's unclear when or if they will be debated. Speaker Joe Straus, R-San Antonio, has called the bill unnecessary and even damaging.

1 / 3From left: Houston Police Chief Art Acevedo, Austin Police Chief Brian Manley, Dallas Police Maj. Reuben Ramirez and San Antonio Police Chief William McManus spoke against the Senate's bathroom bill on Tuesday.(Eric Gay / The Associated Press) 2 / 3Houston Police Chief Art Acevedo and other law enforcement take part in public safety event where they spoke against a proposed "bathroom bill," Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP) 3 / 3Houston Police Chief Art Acevedo, left, and San Antonio Police Chief William McManus, right, stand with other law enforcement in the rotunda at the Texas Capitol as they wait to speak against a proposed "bathroom bill" at a public safety event, Tuesday, July 25, 2017, in Austin, Texas. The Texas Senate has revived a bill mandating transgender Texans use public restrooms corresponding to their birth-certificate genders. (AP Photo/Eric Gay)(Eric Gay / AP)

Police: Bathroom bill is 'solution looking for a problem'

As Texas senators huddled inside a chilly chamber to debate the bill, police officials from across the state met under the hot midday sun to rally against the legislation.

Supporters of the bill, including Kolkhorst, have said it aims to protect the privacy and safety of women and girls in public and school restrooms.

But one after another, law enforcement officials from the state's major cities, including Dallas, rejected that assertion Tuesday. Meeting on the Capitol steps, they protested the legislation, which they said was a "solution looking for a problem."

Maj. Reuben Ramirez of the Dallas Police Department said he had researched data back to 2014 and found no reports of men assaulting women in bathrooms. Even if there were reports, other officials said, there are laws to punish those offenses.

Ramirez added that the bill would make it more difficult for police to do their jobs and would pull resources away from fighting violent crime. He urged legislators to vote against it.

"If you support your police, listen to your police," he said. "There's no need for this legislation."

Austin Police Chief Brian Manley said the bill would be difficult to enforce: "It puts officers in an untenable position, and it works against public safety, and it is not in the best interest of the community."

Senators, debating the bill as the police spoke, peppered Kolkhorst with questions about the law enforcement opposition. When asked about their protest, Kolkhorst said she believed her bill would serve as a "deterrent" against those who contemplate attacking women in intimate spaces.

Staff writers James Barragán and John Savage contributed to this report.