PHOENIX - Members of a special judicial screening panel have asked the Arizona Supreme Court to void a law that would require them to give the governor more names from which to select new judges, calling the legislation unconstitutional.

Attorney Paul Eckstein said a 1974 voter-approved constitutional amendment requires members of the Commission on Appellate Court Appointments to screen applicants for the Supreme Court and state Court of Appeals. That same provision mandates they must send the governor at least three names, though they can send more.

But HB 2600, approved earlier this year by the Republican-controlled Legislature and signed by Gov. Jan Brewer, mandates they must submit at least five names to the governor.

That can be ignored only if two-thirds of the commissioners vote there are not that many qualified applicants.

The law applies the same changes to separate commissions that choose Superior Court judges in Pima, Pinal and Maricopa counties. The other 12 counties still elect their judges directly.

Eckstein wants the high court to declare the law invalid, ruling the Arizona Constitution and its provision allowing the commission to nominate as few as three applicants trumps the legislation.

He also said it's not like lawmakers do not know how to do it right.

Eckstein pointed out the Legislature put a similar measure on the 2012 ballot asking voters to require the nominating commissions to give the governor at least eight names for each vacancy.

Voters said no by an almost 3-to-1 margin.

Rather than risk taking a modified constitutional amendment back to voters, Eckstein said lawmakers decided they have the right to make the changes themselves, which they cannot do.

"Only the people may amend the constitution," he wrote.

At the heart of the fight is the contention by some that the governor should be given more choices.

Rep. Justin Pierce, R-Mesa, sponsor of the legislation, said the Arizona Constitution allows the screening commission to nominate as many people as it wants, but they almost never send more than the required number of names.

And Pierce argued the governor's choices are even more limited because the list must include people from more than one party, which normally means just two names from the governor's own party. He said there usually are far more than three qualified applicants for most vacant slots.

Rep. Eddie Farnsworth, R-Gilbert, said HB 2600 does permit a nominating commission to send fewer than five names, leaving undisturbed the three-name minimum, but only if two-thirds of the commissioners conclude there are not five qualified applicants.

Eckstein said that still amounts to changing the voter-approved constitutional provision.

"Plainly it was not the people's intent to leave the minimum requirement to the discretion of the Legislature," he wrote.

Eckstein won't have far to look if he needs advice making his case to the state Supreme Court. He has signed up six former Supreme Court justices as co-counsel: Stanley Feldman, Charles Jones, Frank Gordon, Ruth McGregor, Tom Zlaket and James Moeller. All but Moeller served as chief justice.