The California Legislature, as noted in this space before, has a penchant for making policy decisions that backfire with unintended, sometimes very damaging consequences -- largely because lawmakers don't take the time to fully explore the potential ramifications of what they decree.

The list of such ill-considered decisions is lengthy, and The Bee's Dan Weintraub has, in a series of recent columns, added another multibillion-dollar blooper to the record: the huge expansion of pension benefits for government workers on the wrong-headed assumption that the Public Employees' Retirement System would generate limitless stock market profits. As Weintraub notes, the state is now stuck with several billion dollars a year in unexpected pension costs.

Having assembled such a sorry record of legislating on false assumptions and unverified claims, one might expect that lawmakers would be doubly or triply wary of acting in ignorance. But the state Senate proved again on Thursday that foolhardiness continues to thrive.

Beyond its big goof on the budget, the Legislature's most wrongheaded decision of recent vintage was its unanimous vote in 1996 to radically alter the way in which electric power would be generated, distributed and priced in California -- the infamous, and ill-named, "utility deregulation" measure that led to the disastrous power crisis in 2000 and 2001.

While those involved in the legislation still defend it and try to blame others -- greedy energy sellers and impotent federal regulators -- for the multibillion-dollar debacle, the fact remains that the mess wouldn't have happened had the California Public Utilities Commission not sought to overhaul energy regulation in the state and the Legislature not passed what it said was an improved version.

Clearly, legislators didn't fully consider the possible ramifications of the 1996 utility measure before rushing it into law with only cursory debate. In fact, a new piece of legislation purports to repeal it.

"We're not mending it, we're ending it," Sen. Joe Dunn, D-Santa Ana, declared as he unveiled the new legislation early this year.

Well, it should be ended. But it appears that the Legislature is paying no more attention to the fine print of the Dunn bill than it did to the 1996 measure and could wind up making another dumb mistake.

The Senate passed Dunn's bill on Thursday, even though he had dropped more than 100 amendments into the measure just one day earlier. Do senators, even Dunn, really understand how the new system he envisions, one in which the Public Utilities Commission regains a central role, would work? He says it would bring price and supply stability to electric service -- but the framers of the 1996 measure also promised huge benefits to consumers.

Several provisions of the Dunn bill make one suspicious that it's aimed not so much at improving utility service as at improving Dunn's prospects of being elected attorney general in 2006 by stroking labor unions and personal injury attorneys, two very influential Democratic interest groups. One passage appears to create new legal "rights" on which attorneys could base lawsuits (Dunn was a prominent trial attorney himself) while another would make the PUC the guarantor of "reasonable compensation" for utility workers.

Republicans complained about the rush. "Folks, we've been down this road before," said Sen. Ross Johnson, R-Irvine, the only current senator who was a member of the body when the 1996 bill was enacted without a dissenting vote. "We ought not buy a pig in a poke on this subject. We ought to know exactly what we're doing."

Dunn responded lamely with "we have much more work to do." In fact, the bill itself declares that, "Notwithstanding any other provision of this act, this act shall not become operative, and is for display purposes only."

Why in heaven's name is the Senate voting on such an incomplete product -- one that probably will surface again in the last frantic moments of the legislative session, as did the ill-fated 1996 bill, after special-interest lobbyists massage its provisions? The Legislature is again elevating rapid action over well-reasoned decision-making, which is why so many of its decrees backfire.