Criminal cases of dubious provenance abounded. One that received great attention involved Margaret Kelly Michaels, convicted in 1988 of rampant sexual abuse at the Wee Care Day Nursery in Maplewood, N.J., where children said she had sexually abused them with knives, spoons and forks, and had urinated in their mouths. None showed signs of injury. Six years later, Ms. Michaels’s conviction was overturned. Another prominent case from those days involved charges of rape and sodomy brought against the operators of the Little Rascals Day Care Center in Edenton, N.C. As with McMartin, there were bizarre allegations early on about babies being murdered and children thrown in with sharks. Though defendants were found guilty, their convictions were later overturned and charges were dropped.

Inevitably, perhaps, the mass frenzy over supposed Satanism and sexual predation invited comparisons to the Salem witch trials and to McCarthy-era excesses. Americans do seem prone episodically to this kind of fever. Witness the widespread panic a few decades ago when people around the country convinced themselves that evil neighbors were handing children poisoned Halloween candy and apples embedded with razor blades. Arthur Miller highlighted this phenomenon in his 1953 play, “The Crucible,” which invoked the Salem trials to comment on a contemporary abuse, the scattershot McCarthy hunt for Communists, much as Hellman had looked to the early 19th century for material about the power of a readily believed lie.

Often enough in these situations, news organizations share blame. In the McMartin case, they were far from innocent observers. A pack mentality set in after a local television journalist first reported the allegations. Across California and beyond, normal standards of fairness and reasoned skepticism were routinely thrown to the wind, with news gatherers scrambling to outdo one another in finding purported examples of monstrous behavior by the principal defendants: Peggy McMartin Buckey and her son, Raymond Buckey. (Ms. Buckey, daughter of the school’s founder, died at 74 in 2000. Raymond Buckey, now in his mid-50s, said years ago that he wanted simply “to be left alone,” and he did not acknowledge Retro Report requests for an interview.) It would be comforting to believe that mindlessly frenetic news coverage is a relic of the past. But who could make that claim with a straight face?

Did McMartin have any lasting effects? In some respects, yes. Teachers across America grew afraid to hug or touch their students, out of fear of being misunderstood and possibly being brought up on charges. A widely held notion that young children do not lie about such matters took a huge hit. Some are vulnerable to implanted memories. In the McMartin case, many jurors found that leading questions from therapists steered impressionable children toward some of the most macabre tales.

Of course, child abuse was then, and is now, an appalling reality in this country. So is false memory. The tricky part is sorting out which is which. If you have wondered whether it is possible that Woody Allen long ago sexually abused his and Mia Farrow’s adopted daughter, Dylan — and who has not wrestled with this explosive accusation and Mr. Allen’s insistent denial? — you readily appreciate the depth of the problem.