Maryland Gov. Larry Hogan (R) talks about the state budget on the steps of the Maryland State House last month. (Katherine Frey/The Washington Post)

FOUR YEARS ago, lawmakers in Annapolis struck a deal to undergird Maryland’s perilously indebted pension fund. The deal rested on a pair of sacrifices: State employees would contribute 7 percent of their earnings into the fund, rather than 5 percent. And the state would reciprocate by chipping in $300 million annually in catch-up payments to restore the fund to a facsimile of good health over the next couple of decades.

Last year lawmakers failed to honor the deal, slashing the state’s contribution in half. This year they did it again, whacking the catch-up payment to just $75 million for the fiscal year starting in July.

Yet when Gov. Larry Hogan (R) put his foot down, insisting on a $150 million payment — still just half the amount approved in 2011 — Democrats in the legislature painted him as a bogeyman and refused to go along.

The Democrats’ hypocrisy is thick, and their arguments are thin. They rest mainly on the supposition that the $45 billion pension fund is already well on its way to recovery and that everyone should just relax if cash is diverted from it to other needs.

They seem sanguine that the stock market will take care of the problem — a problem that still amounts to a nearly $20 billion IOU to current and future teachers, judges and state police who receive monthly checks that provide for their welfare.

The Democrats’ faith that such a debt can be massaged into irrelevance is an irresponsible bet that future taxpayers will clean up a mess that current lawmakers prefer not to tackle. Rather than stay the course set in 2011 — or even half the course — they prefer to raid pension contributions and redirect the money elsewhere.

Mr. Hogan went along with the Democrats’ priorities, up to a point. He allowed a 2 percent raise for state employees, and he released funds for pregnant women and other public health programs. He drew the line at $68 million earmarked by lawmakers to help public schools in high-cost parts of the state.

The governor says he will refuse to spend that money in the coming fiscal year and then redirect most of it to the pension fund, along with surplus cash if it materializes. Democrats may try to block him from doing so; they insist they will stand on principle.

What exactly is that principle? Their prerogative to burden a future generation of taxpayers with deferred debt in an amount the legislature’s own top analyst calls “eye-popping”? The right to take back a promise when pressed to do so by competing interests? If that’s principle, it’s frightening to imagine what political expediency looks like.