LOS ANGELES, SEPT. 21 -- A state judge refused today to reduce Charles H. Keating's $5 million bail, saying he was concerned that the key figure in the nation's most expensive savings and loan collapse would flee.

Bail was reduced for three codefendants named in a 42-count criminal fraud indictment, but Superior Court Judge Gary Klausner said numerous civil lawsuits and the threat of prison gave Keating "significant reasons not to stick around."

After a two-day hearing, Klausner reduced bail to $100,000 each for Ray C. Fidel and Robin S. Symes and $200,000 for Judy Wischer. Fidel and Symes quickly posted checks, but there was no indication that Wischer would make bail. All four have been held in the Los Angeles County Jail since Tuesday.

Keating is the former chairman of Phoenix-based American Continental Corp., which owned the failed Lincoln Savings & Loan of Irvine, Calif. The cleanup of the S&L is expected to cost taxpayers $2 billion. The others were officers in Lincoln or American Continental.

The defense said Keating could not afford $5 million and wanted his bail reduced to $500,000, which his children could post. A Keating son-in-law, Robert Wurzelbacher, listed real estate worth about $500,000 owned by the children, testifying that all were paid for legally. The court required that any money used for bail could not come from criminal activity.

Defense attorney Stephen C. Neal called the high bail "insupportable as a matter of law." He indicated the bail would be appealed.

Under usual California bond practices, if Keating were to go to a bail bondsman for the $5 million, he would pay a non-refundable fee of $500,000 and he or others would have to pledge $7.15 million in property or bank accounts as collateral. The collateral would be returned if Keating made all his court appearances.