When will state lawmakers finally comprehend a fact that high school physics students learn? Every action has an equal and opposite reaction.

With the next session of the Legislature still months away, the grumbling and complaining have already begun in Jackson over Mississippi’s ever-increasing prison budget.

The odd part is, legislation lawmakers approved helped contribute to the problem.

While prison populations are increasing across the country, Mississippi’s is exploding — more than doubling in the last five years.

The problem, many folks say, is the state’s 1995 truth in sentencing law. The law requires inmates to serve 85 percent of their sentence.

Many states have such a law, but Mississippi is the only state that applies it to all prisoners. Most others exclude non-violent offenders.

The law in effect has helped contribute to the prison population boom.

Since its inception, critics have questioned where the money to pay for it will come from.

In the latest round, House Appropriation Committee Chairman Charlie Capps, D-Cleveland, compared the problem to a bad train ride.

”That’s just horrifying. I’m really speechless,&uot; Capps said. ”What can we do as a Legislature to stop this train that’s just knocking us dead?”

The two obvious answers are either to increase the amount of money the state allocates to prisons or to reduce the prison population.

Neither is a sunny prospect.

Tight state finances have put a squeeze on all aspects of state government. Squeezing harder won’t likely create the amount of funds needed.

And few people want to let convicted prisoners get out of jail early.

A decision is looming. And it must be made soon. We hope regardless of the outcome that it becomes a lesson the law of gravity in government: Ignore the long-term effects of an issue, such as funding, and it’s bound to come crashing back to earth — eventually.