"The language of the constitution [and the statute] is pretty clear," Johnson said. That 2004 amendment bans not only gay marriage, but also any marriage-like privileges for same-sex couples.
In late August, The Salt Lake Tribune quoted Johnson indicating that, absent specific legislation, Utah would likely follow the IRS policy that same-sex couples married legally in any state, regardless of their state of residence could file joint returns. That's because the state tax system piggybacks on the federal one.
Johnson said the latest decision against accepting such filings came without any formal vote by the four-member commission, which action he asserted was within the law. But he acknowledged "in retrospect" it might have been better to do so in an open, public meeting, as normally is the case with commission rules and decisions.
"It would be entirely appropriate if somebody wanted to ask us to address this in an open meeting," he said.
Johnson also acknowledged enforcement of the Utah tax policy against same-sex couples filing joint state returns would be difficult, if not impossible.
"I don't know that we'd have any mechanism to catch that," he said. "At this point, we have no intention to put anything on the return to flag that."
Valerie Larabee, executive director of the Utah Pride Center, criticized the sudden decision by the Utah Tax Commission and said she's sure someone will challenge it in court.
"I would guarantee it," she said.
"Utah once again is going to be seen in the national spotlight as a state that doesn't honor the marriages of all of its adults," Larabee said. "With everything going on in our country right now [with the federal government shutdown], this is just over the top."
Clifford Rosky, a law professor at the University of Utah who is also chairman of the board of Equality Utah, said, "it is very unfair, and it will make life very difficult for same-sex couples in Utah."
Essentially, same-sex couples attempting to follow Utah's policy would have to calculate their hypothetical federal tax liability based on what it would have been previously and use it to figure their state taxes.
"To require people to go through the exercise of doing a separate fake federal return is a real burden on people in their everyday lives," Rosky said.
"That's going to be complicated and expensive for them. And, of course, it's unfair because the U.S. Supreme Court has said that people who enter into lawful marriages, gay couples, should be treated equally throughout the country, and so has the Internal Revenue Service."
State Sen. Curt Bramble, R-Provo, is a member of the Senate Revenue and Taxation Committee and a certified public accountant.
"It's very difficult for us to unplug the Utah tax system from the federal," Bramble said. "Some would claim this is a CPA's full employment act. I would favor simplicity."