NEW YORK — THE American Civil Liberties Union Saturday voted to remain neutral on the nomination of Judge Clarence Thomas to the US Supreme Court despite a majority of directors opposing the nomination.The vote by the ACLU national board of directors fell one vote short of the 60 percent majority required by the organization to opppose Mr. Thomas. The final vote was 36 to 25 against the nomination. "The overwhelming majority of the board does not want Clarence Thomas to be confirmed," ACLU spokesman Phil Gutis said. "We will be calling on the Senate to thoroughly probe Judge Thomas's judicial philosophy." He said that during the debate, which he characterized as "emotional," no one argued in support of Thomas. "It's not a question of whether or not Thomas is bad, but how bad is he," Mr. Gutis said. "Our decision to remain neutral in this battle is not in any way an endorsement of Judge Thomas," he added. The debate centered around Thomas's positions on civil rights issues - including abortion rights - that the ACLU has championed. "The debate is whether he meets the standards that the ACLU has set - whether his entire judicial philosophy represents a grave threat to civil liberties," Gutis said. "It's a very high standard," Gutis noted. "It deals with his entire judicial philosophy, not just one or two issues." But with the highest court narrowly divided on abortion rights, Thomas's expected support for overturning the court's ruling legalizing abortions prompted heated discussions. Jane Benshoof, director of the ACLU's reproductive rights project, was among those who denounced the Thomas nomination. Others described Thomas as a muddy thinker who has not proved he deserves a seat on the court.