Suppose it was 1650 and you were accused of being a witch. Would you prefer trial by water or hanging?

If you choose trial by water, the people in charge of things will throw you into the nearest lake, river or ocean and wait to see if you sink or float.

If you sink, you’re innocent, for all the good that does you.

So you may as well choose hanging. With any luck, it will take a good long time before the people in charge of things can agree on where to build the gallows.

That’s exactly the choice the business community in Southern California has faced for the past four years, as the South Coast Air Quality Management District worked up its next four-year plan for air quality management.

In this version of trial by water, businesses are commanded to spend fortunes trying to meet ever-tightening emissions standards, and they are fined to death when they cannot comply.

With hanging, the businesses are offered incentives to walk up the 13 steps and put their own necks in the noose.

The South Coast Air Quality Management District, a powerful regulatory agency with authority over businesses in four counties, held a public meeting Friday to consider its brand new 2016 Air Quality Management Plan, 5,300 pages long.

The plan is part of a complex federal and state regulatory apparatus that’s attempting to achieve “attainment” of federal air quality standards. Unfortunately, the standards are so tough that we wouldn’t meet them even if every source of emissions regulated by the SCAQMD shut down completely.

Business groups support the 2016 AQMP because it relies on incentives to cut emissions, not “command and control” rule-making from regulators. The money for the incentives would likely come from raising your taxes.

Groups with “environmental justice” in their names joined the Sierra Club at the public hearing to denounce the incentive-based plan. They believe that tougher regulations will save lives but not cost jobs.

Everybody should believe in something.

This is a witch trial because businesses have been judged guilty of killing people with invisible particles, and nobody in government wants to hear from legitimate scientists who have done studies demonstrating that this is not true.

That’s because regulations have to meet a standard of cost-effectiveness, and only the value of a human life can justify the crazy-expensive cost of replacing so much equipment over and over again. At Friday’s meeting, an AQMD staffer claimed 1,600 lives are lost per year in the South Coast Air Basin to the health effects of air pollution.

But in letters written in response to the air quality management plan’s appendix on health effects, reputable and accomplished people in the fields of science, statistics, physics and medicine cite evidence that the number of deaths caused by air pollution in California is zero.

What if they’re right?

The 2016 AQMP is wildly expensive. It may lead to higher taxes to pay for incentives to further clean up something that has already been cleaned up. We may see higher prices as a result of higher shipping and energy costs. Even the price of a water heater could shoot up if gas-fired appliances are banned.

Shouldn’t we know for certain whether any of that is really necessary for public health?

Maybe the new EPA administrator in Washington would like to hold hearings. It would be a nice change from witch trials.

Susan Shelley is a columnist and member of the editorial board for the Southern California News Group. Her latest book, “How Trump Won,” has just been published.