Far from the fanfare of Brilab and Abscam, the Justice Department has come up empty-handed after a three-year investigation into political corruption at the state capitol here.

The probe, which came to an end last month when a federal court, at the prosecution's request, ordered an investigatory grand jury discharged, had centered on bribery charges involving state lawmakers and a variety of top corporate and political figures.

In the end, it turned out, some said, to be a textbook example of what not to do. There were no convictions, and only two minor indictments that were later dropped. The political careers of one state senator and a lieutenant governor came to an end and the image of the late mayor of San Francisco, George Moscone, was tarnished. But the one major casualty may be the man who prosecuted the case, Herman Sillas Jr., U.S. attorney for the eastern district of California.

The Justice Department has asked the White House to fire Sillas because of allegations he accepted $7,500 in bribes from a southern California used car dealer and confidence man named Richard Timothy Workman.

The allegations against Sillas were turned up by then-state attorney general Evelle J. Younger, who started his probe when the FBI and Sillas would not share information with the state Justice Department.

Sillas, maintaining his innocence, has refused to resign, and has engaged Los Angeles attorney Cyrus V. Godfrey to represent him.

From the beginning, the California investigations were troubled by press leaks that indicated possibly half-a-dozen state lawmakers as well as representatives of the Howard Hughes corporate empire were under investigation. At the same time, the probe was hampered by a lack of staff.

At the height of the investigation, only nine agents -- three in Los Angeles and six in Sacramento -- were working on the case.

Only two lawyers from the U.S. attorney's office -- Sillas and his top deputy, Malcolm Segal, presented evidence, with the part-time help of Melvin Dildine, lent to them from the Public Integrity Unit of the Justice Department in Washington.

Because of that, sources say, there was a crush of information turned up by agents that could not be presented to the grand jury, which often went for weeks without meeting.

By contrast, an FBI probe of the Pennsylvania legislature a few years ago that culminated in convictions of the state House speaker and state Senate majority leader included 40 agents working full time with five to 10 prosecutors.

"At the intensive stages, you have to have that kind of manpower," said David Marston, then the U.S. attorney for the eastern district of Pennsylvania. "Because more than almost anyone realizes, timing is everything.

"If you can't keep up the initiative, stories get made up, records get destroyed once the targets have had time to get together. You have got to have a full-court press."

Several sources say the team that began the California probe, which started in April 1977 with allegations that an operative for the Hughes empire had given Moscone a $10,000 check through an aide, was ready to go with its case. Moscone was assassinated in 1978 and that portion of the investigation was not pursued.

The special panel then spent nearly a year deliberating whether to indict state Sen. Alfred Song on relatively minor charges, while more important cases were neglected.

Finally, last November Sillas said Song would not be prosecuted. But for him it was too late. Leaked news stories used by a Democratic opponent in the primary had already cost him renomination to his state Senate seat. And that same year, Lt. Gov. Mervyn M. Dymally, a Democrat, was defeated for reelection after his GOP opponent cited newspaper accounts that Dymally was under investigation. Dymally was never formally charged.

FBI agents at first were unaware of the differences between federal and California election laws, which allow local lawmakers to accept contributions from corporate coffers, unlike members of Congress, whose donations are limited and must come from individuals or political action committees.

Thus, for some time, agents followed the trail of corporate contributions to politicians, although those donations were legal.

Despite a wide number of informants, apparently none of them was close to the center of corruption in Sacramento, if there was any. Recently, the agent in charge of the Sacramento probe was asked why no "sting-type" operation was set up in which agents would pose as potential bribers or middlemen. Such an approach was used by FBI in Washington and other cities in the Abscam and Brilab cases. Those cases, disclosed in February, now are being examined by investigating grand juries.

The Sacramento agent replied that the California situation "did not lend itself to a sting-type operation."

According to another federal source, that is an admission that after nearly three years of work, agents were unable to come up with a single informer who could serve as a double agent to plant FBI agents posing as businessmen offering a bribe.