We have an axiom when making election endorsements: The voters have to decide, so we have to decide.

When The News Tribune’s editorial board makes an endorsement decision, we discuss it – and sometimes argue it – until we reach a verdict one way or another.

Exceptions are very rare. But we’ve arrived at one of those impasses this year in the race for state attorney general. We think that both the incumbent attorney general, Republican Rob McKenna, and his Democratic challenger, Pierce County Executive John Ladenburg, are superbly qualified, but in such different ways that it is difficult to compare them directly against each other.

Start with McKenna. And start with the fact that he has run the attorney general’s office successfully since he was elected in 2004.

McKenna is ethical and competent. Like his predecessors, including now-Gov. Chris Gregoire, he has kept the office above partisan politics.

Last month, for example, McKenna charged the Building Industry Association of Washington with illegally concealing political money that now are being used to attack Gregoire. The BIAW is a major Republican ally.

On Friday, McKenna sued the state Republican Party itself over another alleged violation of campaign law. In some states, it would be unthinkable for an attorney general to file a lawsuit against his own party’s interests on the eve of an election.

We also like McKenna’s wholehearted devotion to open government. More than any preceding attorney general, he has been a champion of public access to official records and meetings.

For these and other reasons, Mc-Kenna’s re-election would serve the state well. But we think Ladenburg’s election would also serve the state well.

Open government hasn’t been one of Ladenburg’s passions. On that question, he’d have to prove himself in office.

But Ladenburg has held positions of public trust in Pierce County for many years – eight years as executive, 14 years as the county’s prosecuting attorney and four years as a Tacoma City councilmember.

We’ve seen him up close and have been consistently impressed by his energy, vision and political courage. In one way or another, he has been deeply involved in nearly every major issue affecting Pierce County for the last two decades.

He was one of the engineers of the historic land-use settlement with the Puyallup tribe. He’s been a leader of regional transportation planning and a chairman of Sound Transit. He has been an effective champion of job-creation in the South Sound. He’s played a key role in many other arenas as well.

Ladenburg, too, would make a fine attorney general. It’s the state’s misfortune that only one of these exemplary candidates can win on Nov. 4.