What arrogance. What duplicity.

When Gov. Chris Christie presented his budget last month and trumpeted his $2.25 billion payment into the state pension system, sharp-eyed Trenton watchers were a little puzzled.

Up until that point, the state's "full" pension payment, as required by the pension reforms Christie signed in 2011, had been put at $2.4 billion. But a lot of numbers get thrown around the day of the budget address, and the discrepancy ended up attracting little attention.

Until this week.

Thanks to some excellent reporting by Mark J. Magyar at NJSpotlight.com, we now know what happened.

Without telling the Legislature or the public, the Christie administration had instructed the actuaries who calculated the state's pension payment to change the formula, according to Magyar's March 25 report.

The change, which Magyar found buried in actuarial reports issued two days after the budget address, meant that Christie could change that required $2.4 billion payment in next year's budget to $2.25 billion. And not content to stop there, the Christie administration also retroactively changed the formula for the current budget, so it could cancel a $93.7 million pension payment due in June to plug a hole in that spending plan.

The state's pension system, of course, has a massive unfunded liability. The 2011 reforms, which eliminated cost-of-living increases for pension recipients and forced state workers to pay more toward their pensions, also required the state to make increasing payments over seven years until the system was solvent.

Now, Magyar reported, under Christie's new formula, the state will be putting $900 million less into the pension system over the next four years.

The change in the formula resulted from a unilateral decision by the Christie administration to count state employees' pension contributions at their newer, increased level. At the time the law was passed, Christie and Democratic legislative leaders agreed to count the workers' payments at the previous, lower rate - a fiscally conservative move designed "to make the system a little healthier," David Rosen, the Legislature's chief budget officer told Magyar.

So Christie's move is fiscally unsound - it deepens the hole the pension system is in.

It will rightfully infuriate public employees who have kept up their end of the bargain and expected the state to do the same, not tinker with the formula.

And, in classic Christie style, the move was both arrogant and devious. If he thought the change was justified, why not tell people about it upfront?

All of New Jersey should be outraged.