WASHINGTON — Senate Democrats threatened this week to refuse to seat any new Illinois senator chosen by embattled Gov. Rod R. Blagojevich, but it is not clear the senators have the legal authority to reject a fully qualified appointee.
In 1969, the Supreme Court ruled that the House of Representatives could not refuse to seat Rep. Adam Clayton Powell Jr., a New York Democrat who was accused of putting his wife on the payroll and misusing travel funds to vacation in the Caribbean. Despite those charges, he had been reelected by his constituents in Harlem.
"The Constitution does not vest in the Congress a discretionary power to deny membership by majority vote," wrote Chief Justice Earl Warren. Congress may "judge only the qualifications set forth in the Constitution," he said.
The qualifications are minimal. A senator must be at least 30 years old, a U.S. citizen and "an inhabitant" of the state.
The ruling in the Powell case served as a precedent in 1995 when the Supreme Court struck down term limits for members of Congress. The justices said that states may not add extra qualifications for serving in Congress, including restricting the years of service.
Warren said in his opinion that the Senate's power over its members "is identical" to that of the House.
The court referred to an elected representative; its opinion did not address whether an appointed senator would have the same standing.
But legal experts say the Senate does have the right to look into whether a senator's election or appointment was valid and lawful.
"It's true the Senate cannot add qualifications, but it has to recognize an election or a selection as valid," said Trevor Potter, a Washington lawyer and former chairman of the Federal Election Commission. "If it has questions about that, such as after a contested election and a recount, the senators can delay a decision on seating and defer the issue to a committee."
After the 1974 election, the Senate refused to seat Louis C. Wyman, a Republican from New Hampshire who won in a second recount by two votes. His Democratic rival, John Durkin, objected. He had won the first recount by 10 votes. The Senate voted to send the matter to the rules committee. It too was deadlocked, and the candidates agreed to a special election, which Durkin won.
In Wednesday's letter to Blagojevich, the Senate Democrats warned the governor against choosing a new senator, but they did not flatly refuse to seat such an appointee.
"Please understand that should you decide to ignore [our] request . . . we would be forced to exercise our constitutional authority under Article I, Section 5, to determine whether such a person should be seated," the letter said.
This provision is the one the Supreme Court described in 1969 as having a narrow scope. It says: "Each house shall be the judge of the elections, returns and qualifications of its own members."
If Blagojevich were to select someone to fill the Illinois Senate seat vacated by President-elect Barack Obama, the senators could send the matter to the rules committee to judge the candidate's qualifications. And the appointee, if rejected by the Senate, could go to court and challenge the decision as unconstitutional.