BOSTON--A group of Massachusetts mayors and Democratic candidate for governor John R. Silber united yesterday to oppose the Citizens for Limited Taxation's effort to roll back taxes and fees.

Silber met with mayors at a luncheon, and then Boston Mayor Raymond L. Flynn, who did not attend the session with Silber, held a news conference where he and other mayors warned of cuts in local services if CLT passes.

The CLT petition is Question 3 on the list of referendums on the November ballot.

It would cost the state more than $1 billion in revenue this fiscal year, money Flynn and other mayors said would come at least in part from state aid that helps cities and towns pay for police and fire protection and schools.

But CLT Executive Director Barbara Anderson said state budget cuts won't come about without her petition and that local aid could, in fact, be jeopardized more by its defeat than by its passage.

Anderson also filed a formal complaint yesterday with the Office of Campaign and Political Finance, accusing the state Department of Revenue of violating state law prohibiting state agencies from getting involved in ballot campaigns.

The complaint centered on a report issued Sept. 21 in which the Revenue Department estimated how much local aid cities and towns would lose if CLT were approved by the state's voters.

Silber, who opposes the CLT petition but says he appreciates the anger of voters against state government, said he did not believe the average voter fully understood the initiative's impact on the economy and on local governments.

"I don't believe for one moment that the people have been informed on the nature and consequences of CLT," Silber said.

He said his job is to tell the voters, "Believe me now when I tell you CLT is a bad idea, and if you decide to pass it to send me the message, I'll get the message, I will respect you for having sent me the message, then I will save you from the unfortunate consequences that would happen if I literally implemented your message."

But Anderson said while she does not dispute Silber's intentions to cut government spending without CLT, she does not believe the Legislature will go along with them without the pressure of the initiative petition.

"Without CLT, nobody makes these cuts," she said.

She said Republican candidate for governor William F. Weld '66 is correct in referring to the CLT petition as a tool to help him restructure government.

"You don't send anyone out there without a tool," Anderson said. "You don't send a carpenter out to build a house without a hammer. I think John Silber is going to fail in a lot of things he thinks he can do himself."

But Flynn, who laid to rest rumors that he was considering abandoning Silber for Weld, said, "Passage of CLT would be shortsighted and economically counterproductive."