MADISON — A plan by Republican lawmakers to limit the ability of circuit judges to quickly block their new laws may be unconstitutional, according to the Legislature’s attorneys.

A memo from the nonpartisan Legislative Reference Bureau found that the bill could tread on powers reserved for the courts under the state constitution. It follows a statement from a former Wisconsin Supreme Court justice that she thought such a change would violate the state constitution — a notion a chief sponsor of the bill has rejected.

“For reasons discussed in greater detail below, it appears possible that portions of the bill could be found unconstitutional under the separation of powers doctrine,” the memo reads.

With some of their major legislative achievements thwarted by trial courts in the past two years, Wisconsin Republicans have been looking for ways to reign in local judges, particularly in liberal areas such as Dane County.

Since 2011, circuit court judges have blocked all or parts of laws backed by Republicans that required voters to show photo ID at the polls, limited collective bargaining for public employees and expanded the governor’s power over administrative rules. Under a measure introduced last month, such injunctions would be automatically stayed as soon as they were appealed — meaning laws that were blocked would be put back in effect until a higher court issued a ruling.

Rep. David Craig, R-Big Bend, a chief sponsor of the measure, has said the bill would provide stability. He has noted that challenges to state laws are ultimately decided by higher courts in many instances.

“We’re trying to speed up the process,” Craig said. “One judge elected by one extremely small fraction of the state isn’t going to have ultimate say-so over law.”

But former state Supreme Court Justice Janine Geske has called the bill an outrageous violation of the judiciary’s power.

“To statutorily undo a court order before another court has acted on it is clearly to me an infringement on a court’s independence, and I don’t think it will withstand constitutional scrutiny,” Geske, now a Marquette University Law School professor, said last month.

Geske was appointed to the high court by Republican Gov. Tommy Thompson in 1993 and served until 1998.