SACRAMENTO — A legislative conference committee on Tuesday approved a mix of fee hikes, reserve spending and a one-day-a-month court closure plan that will slice $393 million from the judicial branch budget.

The agreement, secured after weeks of sometimes bitter negotiations among lawmakers, sheriffs, union leaders, lawyer groups and court executives, represents a compromise between those who wanted to shield the branch’s long-term infrastructure plans and those who sought protection for employees facing furloughs.

“All of this together, in a very difficult year, is a reasonable way to protect the operations of the courts,” said William Vickrey, chief administrative officer of the Administrative Office of the Courts.

“Nobody’s happy about this deal,” said Michelle Castro, a lobbyist for the Service Employees International Union, which represents thousands of California court workers. But given the alternatives, she said, “This is a step in the right direction.”

The deal must still be approved by the full Legislature as part of a larger plan, still in the works, to close the state’s $24 billion deficit.

Plans call for workers in the AOC, trial courts, appellate courts and the state Supreme Court to all take one unpaid day a month starting this summer, although courts will have some flexibility. Specifics on the closure are still being negotiated among the branch, lawmakers and labor groups.

Closure plans will also be negotiated at the court level. While many courts plan to furlough workers to save money, others say they have enough funds to keep their employees working even if the courthouse doors are locked.

The plan also relies on reducing security on court closure days for a savings of $23.3 million. It’s still unclear whether every court will be able to do this, however; it depends on courts’ security contracts with individual sheriffs. A source familiar with that aspect of the negotiations said sheriffs departments remain adamantly opposed to the planned closures and are considering legal action.

Branch officials also expect to save roughly $10 million through judges agreeing to furlough one day a month. Many judges have already announced they will give up a day’s pay, but by law no one can force them to do so.

The plan also relies on the judiciary siphoning $45 million over two years from its courthouse construction fund. Judiciary leaders expected to pay for 41 new and rehabilitated courthouses with this money, which will eventually be leveraged for $5 billion in bond funding.

Vickrey said the state has agreed to refund the money by 2014. He said he’s unsure at this point whether diverting the money will delay any projects.

The judiciary also agreed to postpone a new case management system and use the savings to operate courts. The IT project has become a lightning rod for court workers and some judges, who complained it was taking precedence over court operating hours.

The plan also calls for adding a $10 surcharge to an existing $20 court security fee on criminal convictions. An additional $5 in court reporter fees will be paid on civil filings.

“Nobody can be happy about a filing fee increase,” said Nancy Drabble, chief lobbyist for the Consumer Attorneys of California. “But it is $5, so we feel that in terms of our members it’s a relatively small price to pay for access to the courts.”

Assemblyman Mike Feuer, D-Los Angeles, also has agreed to amend his so-called civil Gideon bill to divert $10 in new post-judgment fees — originally meant to pay for lawyers for poor civil litigants — to court operations for two years.

Committee Republicans voted against the detailed spending cuts and fee hikes included in the plan, saying judicial leaders should have more freedom deciding where the $393 million is cut.

“Even if the courts agree with this, I would give them more flexibility,” said Assemblyman Roger Niello, R-Fair Oaks.

The plan’s provisions only require approval from a simply majority of legislators, however, and Democrats, with sizable majorities in both houses, appear ready to approve them.

The committee did agree unanimously to withhold money for judges’ annual cost-of-living increases this year, an amount that would have totaled less than 1 percent of their $178,789 salaries, according to estimates.