THE Unites States Supreme Court has decided that the federal government can withhold revised census data from the California Legislature until the legal battle over its disclosure is settled in appeals court.The California Assembly had filed suit to get the statistics for use in redrawing voting districts for the 1992 elections. "We're definitely going to pursue the adjusted numbers. If we can't use them in '92, we're going to seek their use in '94," says Charles Marson, one of the lawyers for the Assembly. "We regard this as just a delay, not a defeat." In a 6 to 3 vote Tuesday, the high court granted a US Commerce Department request for a stay on release of the census data until the case is decided by the Ninth US Circuit Court of Appeals. The outcome of the case will determine whether 1 million people are added to the federal government's official count of California's population. The revisions would affect the amount of federal aid given to the state and the placement of legislative voting districts. A survey conducted by the US Census Bureau after the 1990 census estimated 5 million Americans were missed in the nationwide population count, many of them in California. However, Commerce Secretary Robert Mosbacher refused to release the revised data. The issue is tinged with partisanship because it is widely believed the census failed to count hundreds of thousands of inner-city residents and racial minorities. A redistricting based on the revised data would give more representation to urban areas, which are strongly Democratic, at the expense of suburbs, which are Republican. The Democratic-controlled California Assembly filed a lawsuit in July under the federal Freedom of Information Act to get the revised census figures. A US District Court judge granted a preliminary injunction ordering the US Commerce Department to release the census data, but issued a temporary stay to give Commerce Department lawyers time to appeal the decision. Lawyers are scheduled to submit written briefs in January and argue the case before the Ninth US Circuit Court of Appeals next March.