Gov. Jay Nixon has continued to make budget cuts based on concerns that the Legislature might do something that could reduce future tax revenues.
Nixon's recent announcement of $400 million of spending restrictions is the latest example of how he has tested the constitutional boundaries of a governor's authority to control the budget.
Nixon says he has clear legal authority, but Republican legislative leaders contend he does not.
At issue is a constitutional provision that allows Missouri governors to "control the rate" of expenditures and to reduce spending below budgeted amounts when revenues fall short of projections.
The state Supreme Court heard arguments in March on a challenge to Nixon's previous budget cuts made in 2011, but has not ruled yet.