She is studying law-enforcement part-time at a junior college and works at a convenience store in Burlington, N.C. Along with soap and soft drinks, the store sells magazines. A man came in the other day and wanted to know if Hustler was in. That journal is not on general display in the store, and the clerk had been instructed to sell it only to those who asked for it. The man had done that. She handed him the magazine, and he arrested her for violating North Carolina's new obscenity law, which went into effect in October to replace a 1973 statute.

The woman will not know until she goes before a grand jury whether Hustler is legally obscene in Burlington. Under the previous law, a "fair warning" hearing was provided at which a judge would decide whether the targeted material went beyond the law. If he said it did, the book store, library or theater could withdraw it without penalty. The new law has deleted the "fair warning" provision, so the woman nabbed by the undercover cop still has no idea whether she broke the law, but she does have an arrest record. And she faces a possible five- year sentence.

The old law also had a statewide standard for obscenity. That's gone too. A book that a jury in Chapel Hill might celebrate as flavorful literature could be judged to carry the mark of Satan elsewhere in the state. This means the citizens of North Carolina have unequal protection under the First Amendment, but the United States Supreme Court said that was okay in the 1973 Miller v. California decision, which is still the utterly confused and confusing guide to the nation concerning obscenity.

Prof. Thomas Tedford of the University of North Carolina at Greensboro is an authority on the First Amendment. His book, "Freedom of Speech in the United States," has been adopted in a number of colleges around the country. Because of the new law, Tedford has stopped teaching a course he's been giving for years. It's an illustrated lecture on the history of censorship of sex, and the graphics include prints from ancient India and China as well as some covers of contemporary Danish magazines.

The new law will not tolerate depictions of people "clad in under garments or in revealing or bizarre costume." Under the old law, Tedford would have been exempt if he could show that his lecture had serious educational value. That defense has also been deleted.

After 19 years of teaching at the Greensboro campus, Tedford is looking for a job outside the state. His idea of teaching does not include the need to keep censoring himself so he can stay out of prison. Michael Curtis, a constitutional lawyer and scholar in North Carolina, told me: "It's possible Tom would win if he were arrested. But would you want to bet three years of your life on taking that chance? The penalties in this new law are so harsh that free speech is being effectively deterred."

Another sharp spur to self-censorship in the new law is a provision making it a felony for adults to view "obscene" material in their own homes. I had thought that the Supreme Court's unanimous Stanley v. Georgia decision in 1969 had preserved the sanctity of the hearth, no matter what those gathered around it wanted to see. But I have been reminded by North Carolina lawyers that Thurgood Marshall, writing for the court in that case, said that "a State has no business telling a man, sitting alone in his own house, what books he may read or what films he may watch." In North Carolina, once your wife or husband sits down beside you to watch, that knock on the door may change your life.

The North Carolina Civil Liberties Union is, of course, protesting this creation of fundamentalist Christians and certain feminists. But what is surprising and quite encouraging to fans of the First Amendment is the awakening of a growing number of college students who have formed Citizens Against Censorship. They also put together a rousing rock concert, "First Aid" (for the First Amendment) in Greensboro. Twelve hundred and seventy-five dollars of the proceeds were donated to the North Carolina Civil Liberties Union.

First Amendment buffs of all ages came to the concert. One, a 62-year- old retired pharmacist, said he wasn't there for the music, God knows. He came to support repeal of the law because "if carried to its full extent, the repercussions of this law could even extend to the Bible." But surely Jesse Helms wouldn't let that happen.