(CNN) -- Some social conservatives are blasting Utah's ruling striking down part of that state's law banning polygamy.
The suit was brought by the stars of the television reality series "Sister Wives," and a federal judge's ruling Friday throws out the law's section prohibiting "cohabitation," saying it violates constitutional guarantees of due process and religious freedom.
Former Republican presidential candidate Rick Santorum -- who a decade ago came under fire for comments indicating polygamy would become legal if courts banned anti-sodomy laws -- responded to the ruling over the weekend.
"Sometimes I hate it when what I predict comes true," the former U.S. senator tweeted Saturday.
The Family Research Council, led by prominent social conservative Tony Perkins, also weighed the Utah statute, warning of "serious consequences of redefining marriage."
"Throughout history, marriage has been future-oriented, focused on the next generation and the best interests of children. The reality is that society needs children, and children need a mom and a dad," Perkins said Monday.
"However, redefining marriage to fulfill the desires of same-sex couples or polygamists only moves society away from this vital public interest and creates social chaos."
In striking down the section of the law Friday, Judge Clark Waddoups used a 2003 Supreme Court landmark gay rights case Lawrence v. Texas, which ruled that anti sodomy laws were unconstitutional.
During that Supreme Court ruling a decade ago, Santorum told the Associated Press that bans on sodomy would open the doors to a "right to polygamy" and other sexual acts.
"If the Supreme Court says that you have the right to consensual (gay) sex within your home, then you have the right to bigamy, you have the right to polygamy, you have the right to incest, you have the right to adultery. You have the right to anything," Santorum said in 2003.
But Waddoups' ruling keeps in place the ban on bigamy "in the literal sense -- the fraudulent or otherwise impermissible possession of two purportedly valid marriage licenses for the purpose of entering into more than one purportedly legal marriage."
Some religious groups also criticized the ruling.
"This is what happens when marriage becomes about the emotional and sexual wants of adults, divorced from the needs of children for a mother and a father committed to each other for life," said Russell Moore, of the Southern Baptist Convention.
"Polygamy was outlawed in this country because it was demonstrated, again and again, to hurt women and children. Sadly, when marriage is elastic enough to mean anything, in due time it comes to mean nothing."
CNN's Bill Mears and Paul Steinhauser contributed to this report.