Car Agency Searched in Probe : Corruption: Dealer supplied luxury autos to Sen. Robbins’ girlfriends. Grand jury is examining the legislator’s efforts to amend a bill affecting rental firms.

SACRAMENTO —  As part of a continuing political corruption investigation of Sen. Alan Robbins, FBI agents armed with warrants searched the Beverly Hills offices of a luxury auto rental agency that supplied cars to the state lawmaker’s girlfriends, The Times has learned.

The May 31 court-approved search was the fourth conducted by the U.S. attorney’s office in Sacramento in connection with its investigation of the San Fernando Valley Democrat, according to sources familiar with the inquiry.

For about three years, federal investigators have been looking at a variety of Robbins’ business dealings, trying to determine whether he improperly used his office for personal gain.

Now, federal authorities are focused on whether Robbins played a behind-the-scenes role in trying to amend a bill on behalf of the car agency at about the time the company was making cars available to the veteran lawmaker’s girlfriends, the sources said.

One of the women, Cynthia Kay, told The Times earlier this year that the agency, The Beverly Hills Car Collection, provided her with a red 1980 Mercedes coupe and that she paid nothing for use of the vehicle--until she and Robbins broke up. Later, a new boyfriend bought the car, Kay said.

Allan J. Siemons, the president of the agency, lobbied against a 1988 bill by Assemblyman Lloyd G. Connelly (D-Sacramento) that, as initially drawn, would have limited the ability of car rental companies to recover damages from their customers.

A week before the FBI raid, Connelly and three legislative staff members said they testified before a federal grand jury investigating Robbins. One of the aides, who asked not to be identified, said he was questioned about an amendment to the Connelly bill sought by Robbins that would have exempted agencies such as MDR Enterprises, which rents out expensive cars through the Beverly Hills Car Collection.

The aide said he testified to the effect that the section “almost became like the Robbins amendment” to the Connelly bill. Eventually, the bill was amended in a way that did not stop any rental agencies from recovering damages.

The aides also said the federal prosecutors sought to establish “that Robbins tried to influence the bill assignment” by attempting to persuade the Senate Rules Committee to send the measure to the Senate Insurance, Claims and Corporations Committee, which Robbins chairs. Ultimately, Robbins did not succeed and the bill was heard in another committee.

Neither Siemons nor Robbins could be reached for comment this week.

Michael L. Lipman, Robbins’ lawyer, said his client continues to deny any improprieties, but declined further comment, saying “it’s inappropriate to get into a jousting match in the press.” Siemons’ attorney, Richard Henry Kirschner, said: “My client has not done anything wrong. The government has a logic all of its own (in conducting a search).”

Kirschner said he was “not at liberty to discuss the situation” but maintained that his client was not the target of the inquiry. He added that Siemons is cooperating “with whatever investigation is going on.”

To obtain the search warrant, prosecutors had to persuade a federal judge of probable cause to believe that a crime had been committed and that the search would likely turn up supporting evidence.

Last November, agents from the FBI and the Internal Revenue Service searched Robbins’ home as well as the residence of California Coastal Commissioner Mark L. Nathanson. Those searches grew out of a grand jury investigation into allegations that the two used their offices to extort $250,000 from a San Diego hotel developer--a charge denied by attorneys for both public officials.

At about the same time, federal investigators conducted a third search at the offices of a public relations firm in Santa Monica, run by a former Robbins aide, Jennifer Goddard. The firm made payments at Robbins’ request to Kay and other girlfriends, according to several sources, including the women themselves.

The records of the searches--along with documents describing the alleged criminal activity--have been sealed by the court.

The latest raid came a week after the U.S. Supreme Court decided a West Virginia case that is likely to have an impact on federal prosecutions of political officials throughout the country. In that case, the justices concluded there must be an explicit promise to act in return for some benefit in order to convict an official under the federal anti-extortion statute. However, the court limited its ruling to the question of campaign contributions.

Even so, the ruling sparked speculation in the Capitol that the federal political corruption investigation will be slowed or even halted. So far, the inquiry has resulted in the convictions of former Sens. Joseph B. Montoya and Paul B. Carpenter on extortion and racketeering charges. Attorneys for the two men maintain that the Supreme Court ruling will result in reversal of the convictions, which are under appeal.

The search of the car rental agency in connection with the Robbins probe is the first clear sign that prosecutors in Sacramento are continuing their investigation, despite the Supreme Court decision.