EDITORIAL DECLARATION OF WAR CITY HALL OFFERS THREATS, NOT SOLUTIONS, TO SECESSION QUESTION.

WHEN politicians need to reveal some shameful deed, they often wait until Friday. That way, news of their treachery is likely to get lost in the weekend hubbub. On Monday, they can try to act like nothing happened.

Last Friday, the outgoing and incoming mayors of Los Angeles, Richard Riordan and James Hahn, both resorted to this cynical political deception.

The two politicians declared war on the Valley secession movement by launching an all-out attack on whether nearly 1.4 million residents of the San Fernando Valley can financially support a government of their own.

And even worse, they questioned the legality of virtually any scenario for Valley cityhood, thereby suggesting they will resort to the courts to try to block a vote of the people.

This may be Riordan's parting gift to the city: A fat 869-page attempt to undermine the secession movement.

The report, produced by the city Office of Administrative and Research Services, was a response to the Local Agency Formation Commission's study that showed secession to be viable and not harmful to L.A. or the new Valley city.

The OARS report is filled with the can't-do mentality that has long plagued City Hall and kindled thoughts of secession. It argues that sharing water and power resources between the two cities would be impossible, and demands that secession accounting be rigged in L.A.'s favor.

It even makes the laughable claim that an independent Valley wouldn't deliver services as efficiently as the infamously wasteful and lethargic Los Angeles bureaucracy.

The document is a testament to the city government that produced it: obstructionist, convoluted and dishonest.

These are obviously not the qualities by which Riordan, who reportedly fancies himself the next governor of California, would like to be remembered - thus the Friday release.

The timing also worked well for Hahn, who no doubt would rather hide his anti-secession study from the Valley moderates and conservatives who elected him.

His city attorney report contends that Valley VOTE's secession plans are illegal, setting the stage for legal action. That's a remarkable turn- around for Hahn, who maintained throughout the campaign that he would do nothing to secession from coming to a public vote.

His flip-flop may well mark an historical first: A politician betraying his campaign promises before taking office.

Hahn and Riordan are faithful defenders of the downtown power structure. They'll protect the status quo even at the expense of fair and honest government - so long as they can do it on a Friday.