Utah polygamists can party like it’s 1889.

The Utah Senate on Friday gave final approval 27-0 to a bill that would reduce polygamy among consenting adults to an infraction — an offense below some traffic tickets — essentially decriminalizing the practice.

Gov. Gary Herbert has indicated he will sign the measure. If he does not, there appear to be enough votes in the Legislature to override a veto.

The bill, SB102, represents a historical shift in how Utah has regarded polygamy, which has been a felony (even for willing participants) for most of the state’s history. The current law makes polygamy punishable by up to five years in prison. It can be up to 15 years if the polygamists are found to have committed fraud, domestic violence, sexual abuse or human smuggling.

(Trent Nelson | The Salt Lake Tribune) Shirlee Draper of Cherish Families speaks, seated next to Sen. Deidre Henderson, R-Spanish Fork, at the first public hearing for SB102, which would make polygamy between consenting adults an infraction (punishable by a ticket but no arrest or jail time) instead of a felony, on Monday, Feb. 10, 2020. On the screen at upper left is a photo taken in a plural marriage home showing seven of the family's children who have served in the military.

The new measure would do nothing to change the stiffer category. And while polygamy among consenting adults still would officially be a crime in Utah, the bill’s sponsor, Sen. Deidre Henderson, R-Spanish Fork, has said her intent was to lessen the penalties to dissuade law enforcement from pursuing charges against people who are breaking no other laws.

Sarah M.S. Pearsall, professor of American history at Cambridge University, said SB102 represents a big change for wives, husbands and children in polygamous households in Utah, especially since the practice has been viewed as “barbaric and unacceptable” since the earliest American colonies.

“It [also] is a significant change in the history of American marriage,” Pearsall wrote in an email to The Salt Lake Tribune, “since it enshrines the principle that consenting adults should not be treated as criminals for choosing to live in plural marriages.”

(Trent Nelson | The Salt Lake Tribune) Sen. Deidre Henderson, R-Spanish Fork, speaks with polygamy advocate Anne Wilde after the first public hearing for SB102, which would make polygamy between consenting adults an infraction (punishable by a ticket but no arrest or jail time) instead of a felony, on Monday, Feb. 10, 2020. At rear are Joe and Valerie Darger.

Henderson framed the legislative discussion in terms of keeping women and children safe from people who commit crimes within polygamy.

“In these isolated, insular communities, that’s where a lot of the problems can really escalate,” Henderson told reporters earlier this month. “And that’s where the bad people can really — and have — weaponized the law in order to keep their victims silent and isolated in their control.”

Ryan Fisher of Sound Choices Coalition, which tries to educate the public on what it sees as the harm of polygamy, issued a statement in anticipation of SB102’s passage. Fisher said the Legislature has not listened to victims from polygamous abusers.

“Senator Henderson and those that pushed this bill,” the statement said, “are recklessly trying to change history before they understand the consequences of the decriminalization and subsequent spreading of polygamy and the harms to men, women and children that are inherent in this social system.”

Polygamy was a common practice among followers of The Church of Jesus Christ of Latter-day Saints, who settled Utah in the mid-19th century. It expanded greatly under the faith’s second prophet-president, Brigham Young, perhaps the Western world’s most famous polygamist.

The church officially began to abandon plural marriage in 1890 as a condition of statehood. The Utah Constitution still says “polygamous or plural marriages are forever prohibited.”

The LDS Church excommunicates members found practicing polygamy. Most of Utah’s modern polygamists still trace their beliefs to the teachings of Mormon founder Joseph Smith.

Trent Nelson | The Salt Lake Tribune Brielle Decker at the former home of Warren Jeffs in Hildale, Wednesday April 5, 2017.

Brielle Decker, the 65th wife of Fundamentalist Church of Jesus Christ of Latter-Day Saints leader Warren Jeffs, is ambivalent about the bill. She acknowledges plural families are afraid to report crimes to police and doesn’t expect that to change.

“They’re not going to just uphold the law all the sudden,” Decker said. “Polygamists always think they’re above the law.”

Jeffs is serving a sentence of life plus 20 years in a Texas prison for crimes related to sexually assaulting two girls he married as plural wives. He is one of the bad polygamists both sides used in arguments for and against SB102.

Some of Jeffs’ former followers, including Hildale Mayor Donia Jessop, said people who did not participate in his sex crimes were afraid to leave the FLDS and seek social services for fear it would expose their family to prosecution and having children removed from homes. Other former FLDS followers, including a Jeffs nephew, Ian Jeffs, said any lessening of the penalties would only embolden abusive polygamous leaders.

(Trent Nelson | Tribune file photo) Sen. Deidre Henderson, R-Spanish Fork, listens to comment at the first public hearing for SB102, which would make polygamy between consenting adults an infraction (punishable by a ticket but no arrest or jail time) instead of a felony, on Monday, Feb. 10, 2020.

The bill passed the Senate the first time with zero no votes and won in the House, 70-3. The House made one amendment — clarifying that sexual battery within polygamy is punishable by 15 years in prison, too — that required another approval from the Senate on Friday.

Herbert made mention of the bill’s broad support on Capitol Hill during his monthly news conference Thursday.

“With marriage laws being what they are today,” the governor said, “and the liberalization of and more broadening of it, eliminating [polygamy] from being a felony to a lesser offense is probably warranted.”

Reporter Lee Davidson contributed to this article.