The U.S. Court of Appeals here upheld yesterday the validity of a search warrant used by the FBI in its massive July raid on Church of Scientology offices here.

In reverting a decision by a lower court judge who had found the warrant improperly drawn, the appeals court said the judge had given an "overbroad construction" to the warrant, "improperly interpreted the relevant offenses." "ignored a significant part" of the warrant, and "unduly" restricted his interpretation of the applicable Supreme Court case. The lower court had ordered documents seized returned to Scientology officials, but the government appealed.

The appellate panel noted that it had taken the unusual step of actually reviewing some of the documents seized inthe raid. It said in its opinion yesterday that the material included apparently original Internal Revenue Service files, CIA documents marked "secret," and files on bugging and locksmithing.

The raid at the church's offices here was one of two conducted by the FBI against the church in connection with an investigation of alleged conspiracies by Scientology officials to infiltrate government agencies, burglarize government offices, "bug" government meetings, steal government property and obstruct criminal investigations.

The other search was conducted in Los Angeles, where the church has two other major headquarters.

Shortly after the day-long raids on July 8, to which hundreds of FBI agents were assigned, attorneys for the church sought to have the searches ruled illegal.

U.S. District Chief Judge William B. Bryant ruled in favor of the church here, saying the warrant was unconstitionally broad because of a certain phrase used in describing the material that could be taken.

Church attorneys then convinced the Los Angeles federal judge who was considering the validity of the warrant there that he was bound by Judge Bryatt's opinion here since the same wording was used in both warrants.

The warrants were based on information supplied to federal investigators by a former Scientology official who has reportedly, admitted breaking into government offices and copying documents, and said he knew of several others persons who conducted similar missions for the church.

The warrant used in Washington listed 148 specific items that were sought. In addition to sought other material and its final paragraph authorized agents to seize "any and all fruits, instrumentalities, and evidence (at this time unknown) of the crimes of conspiracy, obstruction of justice and theft of government property."

Judge Bryant ruled that this language was so broad that it amounted to a "general warrant" - authority to seize anything and everything at the discretion of the agents - and that it therefore violated the guarantee of the Fourth Amendment of the U.S. Constitution against "unreasonable searches and seizures."

The appeals court said Judge Bryant ignored the further language of the warrant that said that the material to be seized had to be supported by other facts in the affidavit accompanying the warrant.

The appeals judges - U.S. Circuit Judges George MacKinnon and Roger Robb and U.S. Customs and Patents Appeals Judge Howard T. Markey - said there was enough specificity in the affidavit to support the validity of the warrant.

The appellate panel ordered the documents returned "forthwith" for use in connection with an a continuing grand jury investigation into the alleged conspiracies.

However the court made it clear that Scientologists could continue to raise other issues they have brought in the past concerning the legality of the manner in which the search was conducted.

The Scientologists have contended that the raids were part of alleged decades-long, and that the FBI used unnecessary force during the execution of the warrant in rifling church files.

The Appeals Court said its order does not stop the lower court from finding that specific documents might have been illegally seized, but asserts merely that the warrant supporting the search was legal.

Church spokesman Hugh Wilhere said last night the appellate court decision "opens the door to the rise of a police state in America."

He said the church plans to attempt to appeal to the Supreme Court, and would continue to press its other challenges to the legality of the search.