By staying in session more than 120 days, Arizona legislators are costing taxpayers nearly $1,200 per day in per diem expenses.

PHOENIX — The Arizona Legislature is now in overtime.

But unlike other jobs where OT equals more money, lawmakers will get less.

And that’s by design: Arizona’s founders wanted legislators to come in, do the state’s business and go home — perhaps before they could think of other improvements to make in the statutes.

State lawmakers are entitled to a per diem allowance, which is designed to pay for out-of-pocket expenses for coming to the Capitol. That’s on top of the $24,000 a year in salary for what is supposed to be a part-time job.

Mind you, there’s no actual requirement to prove the expenses. And the allowance continues even on days when lawmakers don’t go to the Capitol, including Saturdays and Sundays.

For out-of-county lawmakerse, that may make sense if they have to rent an apartment or a hotel room in Phoenix. That’s why the 25 out-of-county members of the House and 12 in the Senate get $60 a day.

But here’s the hammer: State law says that full allowance runs only for the first 120 days of the session. Tuesday was Day 121.

Now that out-of-county allowance goes to $20 a day.

Th 35 in-county House members and 18 senators who don’t need local accommodations were still entitled to $35 a day; now they will get $10.

But it would be wrong to look at that as a savings for taxpayers.

Had lawmakers finished their business within the 120 days, there would be no per diem payments at all.

And each day they’re here from now on still costs taxpayers $1,170 until they go home.

Part of what’s holding up the end of the session is the dispute on how to spend the more than $11 billion in revenues.

It’s not even a partisan divide, with many GOP lawmakers unwilling to accept the proposals of Republican Gov. Doug Ducey.

Other issues range from whether to let the state keep a “windfall” of income tax revenues generated by a change in federal tax law, to whether to give victims of child sex abuse more time to sue their assailants.

So when will lawmakers go home?

The longest session on record was 1988, when it extended beyond June 30, a few days into the new fiscal year.