Utah legislative leaders followed through on their promises throughout the lawmaking session that ended earlier this month that they would move to bolster the power of the Legislature in relation to the other branches of government — particularly the executive.

On Tuesday, Gov. Gary Herbert followed through on his threat to veto such balance-tipping bills and struck down two of them aimed at giving lawmakers more say and muscle in defending the laws they make.

The governor vetoed HB198, which sought to force the state attorney general to give the Legislature a written legal opinion when requested — as already required by state law. He also vetoed SB171, which attempted to authorize lawmakers to mount their own defense of state laws when challenged in court — a duty now exclusively carried out by the attorney general.

It’s unclear, though, whether the Legislature will move to override the vetoes with two-thirds of the votes in the House and Senate.

Herbert said in a letter to Statehouse leaders that allowing legislators to prepare and argue their own legal strategy in challenges to state law would be “akin to the governor filing his own bills.”

“This is contrary to fundamental notions of separation of power,” he wrote, adding that “the Legislature may not exercise executive authority even when the Legislature believes that the executive is not performing its role properly.”

While legislators have suggested that they would use the power to intervene in court sparingly, Herbert noted that SB171’s language is so broad that it could be used to act in “thousands of cases.” And he pointed out that the Legislature appropriated $700,000 to fund such efforts — enough to pay for three attorneys, a paralegal and a legal secretary.

It’s unclear whether SB171 was a response to any particular court case or whether it simply was an effort to give the part-time Legislature greater powers in relation to the full-time executive, as House Speaker Greg Hughes had called for in his remarks opening the session.

HB198, meanwhile, was clearly a reaction to Attorney General Sean Reyes’ refusal last year to hand over a legal opinion he had prepared at the request of lawmakers regarding the governor’s calling of a special congressional election to fill the U.S. House seat vacated by former Rep. Jason Chaffetz.

Reyes said he was constrained from providing the opinion because the governor’s office had warned that doing so would be a violation of attorney-client privilege after the attorney general had consulted the Herbert on unilaterally setting the rules and timetable for the election. (He did disclose the opinion — basically agreeing with the governor’s election-calling powers — months later, after getting the OK from Herbert.)

That refusal infuriated lawmakers, who pointed out that state law requires the attorney general to write and deliver legal opinions to the Legislature upon request.

HB198 sought to strengthen that requirement by allowing the Legislature to ask the state Supreme Court to force the attorney general to comply and to require the attorney general to avert a potential conflict in the first place, through confidentiality and screening safeguards.

SB171 and HB198 both passed the House and Senate with two-thirds majorities that, if supporters stood firm, would be enough to override the vetoes.

Sen. Stuart Adams, R-Layton, and Rep. Merrill Nelson, R-Grantsville — who sponsored SB171 and HB198, respectively — said they needed more time before deciding whether to try for a veto override, although they acknowledged the possibility.

Nelson said he understood Herbert’s motives for vetoing HB198, and he said he’d consider the override option, but it isn’t a “foregone conclusion.”

Instead, he said, the veto might be an opportunity “to reconsider whether there might be a better approach to meet the needs of both branches of government.”

Adams, too, said he understood the governor’s decision to veto his bill, although he said he doesn’t believe SB171 is a “separation-of-powers issue.”

Adams said his bill would allow the Legislature to intervene in lawsuits, which the branch already does frequently.

“We wanted to make sure we can do it as a matter of right,” Adams said. “That’s an appropriate action. I think we see it just a little bit different, but I understand his veto.”

House Majority Leader Brad Wilson, R-Kaysville, predicted Tuesday night that the Legislature will try to override Herbert’s vetoes of the bills designed to give legislators more power.

He was traveling, but he texted to The Salt Lake Tribune: “My perspective is that we will be having an override session.”

“Whenever you have a legislative body elected by the citizens of Utah that overwhelmingly passes two bills with significant long-term consequences for how the state operates, a veto override session is appropriate,” Wilson texted.

“Look at how the U.S. Congress has ceded power to the executive branch in Washington, D.C. and how well that has turned out,” he added. “Defining the roles each branch of government owns is fundamental to the success of our state.”

Each chamber’s leader stood by the measures and said lawmakers would discuss the idea to override the veto.

“Both bills were carefully crafted,” said Senate President Wayne Niederhauser, R-Sandy. “There is some strong legal basis for them. But I can’t predict whether the body will be passionate enough to come into an override margin for them.”

He added that perhaps they “need to be refined a little bit.”

Hughes said that because of the overwhelming bipartisan support the measures earned, "I would hope that both bills would be candidates for an override."

He also said no one takes offense when the governor vetoes a bill or two, but legislators can sometimes be wary of overriding the governor, so he was unwilling to make a prediction — though he wouldn't second-guess them.

Reporters Paighten Harkins and Lee Davidson contributed to this story.