Claiming Gov. Doug Ducey acted illegally, the former chairman of the Arizona Libertarian Party has sued to give voters a say in who replaces John McCain — and soon.

Michael Kielsky acknowledges that the U.S. Constitution allows the governor to name an immediate replacement on the death or resignation of any sitting senator.

But Kielsky, in a lawsuit filed here, contends that the governor is required to schedule a special election as soon as practicable to fill the post. And that, he said, means within six months.

Instead, Ducey said Jon Kyl, whom he named to the post, can serve until after the 2020 general election.

“It really comes down to common sense,” Kielsky told Capitol Media Services.

“If there’s four or five years left, to have somebody sit as a substitute for more than two years is excessive,” he said. “And there’s no reason the government couldn’t call a special election within a reasonable amount of time.”

Gubernatorial spokesman Patrick Ptak called the lawsuit “frivolous.”

“The governor executed the law as required,” he said.

That’s true. Arizona law allows an appointee to serve until the next election. But if that election is not within six months, then that person, who has to be of the same political party as the former senator, can serve until the election after that.

In this case, McCain died on Aug. 25. That was just three days before the primary and 73 days before the general election.

But Kielsky, representing two registered Democrats, one Republican, one Libertarian and an independent, said that misses the point of the lawsuit. He contends the statute used by Ducey to name Kyl is itself unconstitutional.

At issue is the 17th Amendment to the U.S. Constitution. Adopted in 1913, it took the power to name U.S. senators away from state lawmakers and gave it directly to voters.

It says when there are vacancies, the governor “shall issue writs of election to fill such vacancies.” Ducey has done that, setting the primary for Aug. 25, 2020, and the general election for Nov. 3 that year.

Kielsky, however, argues that the Constitution requires the appointment to be temporary “until the people fill the vacancies by election as the Legislature may direct.”

“The state Legislature has no authority to mandate that a temporary appointee shall serve in lieu of or in preference to a senator directly elected by the people beyond any period necessary to hold an orderly election,” he said. And Kielsky called it “well established that an orderly schedule for election of a senator can ordinarily take place within six months.”

A 2019 election would mean voters could choose from anyone of any political party — or no party at all — rather than keeping a Republican in office until the end of 2020.

He said if Ducey had acted in accordance with that timetable the special election could have been in March, when some other issues will be on local ballots anyway. But even if that were not the case, Kielsky brushed aside the costs of holding a statewide vote.

“That’s kind of the job,” he said.

The lawsuit asks Judge Diane Humetewa to direct Ducey to issue an order setting an election no later than six months from when she acts.

Ptak, however, said the governor believes that the law which allows him to appoint someone until after the 2020 election is constitutional.

There’s a complicating factor in all of this.

When Kyl took the appointment he said he was promising to serve only until the new Congress convened in January.

If he quits, that gives Ducey the chance to appoint a replacement. And even if Humetewa sides with Kielsky, that would move any election to six months beyond the date of that new appointment.

“It’s a moving target,” Kielsky conceded. “Nonetheless, the issue remains the same, which is, no, I don’t think we should wait until 2020 for Arizona’s electorate to have a voice in who the next U.S. senator’s going to be.”

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