Where's the 'peace dividend' for low, low crime rates?

The Midland-based Mackinac Center raises some interesting questions about why taxpayers are not seeing any savings in the state budget as the rates of violent crime and property crime are at their lowest levels in decades.
They cleverly refer to this phantom windfall as the "peace dividend" -- as in the U.S. peace dividend that never materialized after the end of the Cold War. 
The center's James Hohman writes:

"The $2 billion Department of Corrections budget has barely budged despite the fact that the prison population has fallen 15.6 percent from 2006 to 2015 – which ought to mean lower costs.

"With fewer prisoners, there are also fewer corrections officers. The number of full-time equated positions in the department was reduced from 17,782 FTEs in fiscal year 2007 to 14,179 FTEs budgeted for FY 2015."

The reason why 3,600 less employees in one department doesn't translate into savings? The so-called dividend has been eaten up by rising health care costs -- for employees and for prisoners -- and the state's ongoing effort to catch up with an underfunded pension and retiree health care system.

I'ts always something.