Gov. Mark Dayton's veto of the budgets of the Minnesota House and Senate will force them to shut down operations and furlough hundreds of workers by the end of August, according to new court documents filed Thursday in the Legislature's lawsuit against the governor.

The clash between the executive and legislative branches of state government heads to court Monday, when attorneys representing the Legislature will argue that Dayton's action was unconstitutional and could put the state's finances at risk. Dayton's legal team, meanwhile, will contend that the Republican-majority Legislature trapped the DFL governor into signing budget bills he believed would harm the state, leaving him with little recourse other than his veto power.

In the legal briefs, the Legislature asks Ramsey County District Judge John Guthmann to grant a temporary injunction that would force the state to continue funding the House and Senate after their budgets run out June 30.

If that doesn't happen, the Legislature says the Senate, which spends about $2.5 million per month, can operate on reserve funds until July 27. After that, all 67 elected senators and 202 of its 205 full-time staff members would be furloughed without pay. The House, with a $2.7 monthly budget, can keep the lights on until Aug. 31, when it would furlough 134 elected lawmakers and 213 of 232 staff members.

The Legislature argues that those cuts, along with the Senate's inability to make monthly lease payments on the new Senate Office Building, amount to the governor effectively shutting down a separate branch of government and potentially putting the state's credit ratings and borrowing power at risk. The Legislature's attorneys also raise the prospect that the Senate could end up evicted from its new building without the ability to make payments.

"The governor's vetoes will wreak significant and widespread financial harm upon the Legislature and the state as a whole," reads one of the Legislature's briefs.

Dayton's attorneys contend that the governor was well within his constitutional rights to issue the line-item veto. They say it was the result of a chain reaction of events that began with the Legislature sticking a "poison pill" into the budget bills funding state government departments and operations.

Republican leaders, seeking to ensure that Dayton would sign a $650 million tax-cut bill he disliked, linked funding for the Department of Revenue in the state government bill to Dayton's signature on the tax bill. Dayton signed the bill but vetoed out legislative funding, in an attempt to bring lawmakers back to the table to reconsider tax cuts, teacher licensing standards and driver's licenses for undocumented immigrants.

The governor's attorneys wrote that the Legislature's move left Dayton with little choice: "if he vetoed the tax bill, there would be no appropriation for the Department of Revenue, but if he signed it, it would imperil the State's fiscal stability and three provisions to which he had serious public policy objections would become law."

Dayton is being represented in the case by Sam Hanson, a former Minnesota Supreme Court justice, while the Legislature's legal counsel is Douglas Kelley, a former federal prosecutor. Taxpayers will pick up the tab for both sides; Hanson is charging $506.25 per hour, while the Legislature will pay Kelley $325 per hour.

Erin Golden • 612-673-4790