From time to time, liberals are challenged as to whether they pass Oliver Wendell Holmes's test of a true civil libertarian: Do they support freedom of thought and speech for those they hate?

Some liberals fail that test. As in the 1970s in Mississippi when the Ku Klux Klan -- having been refused a permit to hold an anti-integration rally in the yard of a newly integrated public school -- turned to the state ACLU for help. The board of that affiliate, badly split, finally acknowledged the Klan's First Amendment rights. Angrily 10 of the 21 board members resigned, including the seven black members.

Now, liberals and civil rights activists in Georgia have been presented a test of their devotion to freedom of speech and association. Once more, the Klan is providing the unbidden challenge.

Last February, Shade Miller Jr., unemployed and a member of the Invisible Empire, Knights of the Ku Klux Klan, told authorities that he was going to violate a 1952 Georgia law. The statute forbids the wearing of "a mask, hood, or device by which any portion of the face is so hidden ... {as} to conceal the identity of the wearer." It was aimed specifically at the Klan because, as one Georgia Klan watcher puts it, "A Klansman in a Klan mask does have an organizational history of violence." Take off the protection of anonymity, the theory goes, and the violence will recede.

It was Miller's contention that if he did not wear a mask while a member of the Klan, he would be an endangered pariah in the community. Accordingly, to try to preserve his anonymity through a lawsuit, Miller drove his pickup to the county courthouse in Lawrenceville, put on his mask and hood and was arrested. He was subject to a $1,000 fine and a year in prison for breaking the law.

For his defense counsel, Miller obtained Michael Hauptman, president of the Georgia affiliate of the American Civil Liberties Union. Hauptman, however, is trying this constitutional case on his own. He anticipated, he toldme, a certain degree of dissidence within the Georgia ACLU if he tried to bring it into the case, so he spared those civil libertarians the Oliver Wendell Holmes test.

Hauptman, based in Atlanta, listens to his own drum as a lawyer. He has represented the outspoken civil rights loner, Hosea Williams, as well as witch doctors, the homeless and, as the Atlanta Constitution puts it, "a parade of candidates for the electric chair." Or, as Hauptman himself says, "I've represented all kinds of bad people ... I even once represented an insurance company and a bank."

Hauptman was not quite sure how this case would come out, in view of his client's choice of associates. But the constitutional principles involved were clear to the stubborn attorney: the Constitution belongs to everyone, even the most odious among us, and if a forced unmasking makes the right to speech and assembly perilous, that law has to be unconstitutional.

Judge Howard Cook of Gwinnett County State Court has agreed. The Klan, he said, "is in effect a persecuted group in that its beliefs may be so abhorrent to most members of society that the Klan members and their families may be in the same amount of danger ... as the black members of the NAACP in NAACP v. Atlanta." (That was a 1958 case in which the state of Alabama unsuccessfully tried to force the NAACP to turn over its membership list.)

The Georgia unmasking law, the judge added, "violates freedom of speech, free association and equal protection guarantees, as well as being vague and overbroad, and is therefore unconstitutional."

An appeal has been taken to the Georgia Supreme Court, and the case may eventually present the United States Supreme Court with the Holmes test.

Highly critical of the judge are, among others, the regional NAACP, the Anti-Defamation League and the Southern Poverty Law Center. They and others predict a considerable resurgence of violence by the Klan. For instance, David Fuller, assistant Gwinnett County solicitor, warns that the decision will allow the Klan to return to the murder and vandalism of 40 and more years ago.

These predictions, however, ignore the fact that law enforcement in Georgia is no longer as it was -- when the cops and the Klan were not exactly adversaries.

Threats that the Klan will be unleashed by the First Amendment show no confidence in Georgia law enforcement authorities or in the Constitution itself.