A SERIAL KILLER pleads guilty to eight murders and is sentenced to 20 years' probation, the first five in home confinement. It sounds like a caricature of lenient justice, yet it happened Monday in Philadelphia.

The murderer is a 70-year-old woman named Marie Noe; the victims were eight of her children, each of whom she smothered as infants. These deaths, which occurred between 1949 and 1968, were then believed to be cases of what is now called SIDS -- Sudden Infant Death Syndrome. They were not. Ms. Noe now admits that it was she, not any disease, who killed eight members of her family.

If these children had been a little older, such a sentence would be unthinkable. According to the Associated Press, an assistant district attorney last year called Ms. Noe "as much a mass murderer as Ted Bundy." It's hard to imagine that any prosecutor would have tolerated a sentence with no prison time for Mr. Bundy, who was, after all, sentenced to death and executed. Serial killers, once convicted, at least go to jail.

The reality is, however, that while few people would be caught saying aloud that the murder of eight infants is somehow less deserving of punishment than the killing of eight young women, we seem to have a way of treating baby killers more gently than other murderers. It is a pattern that we have seen locally, where a woman was sentenced to weekends in jail for three years for killing her infant daughter and was subsequently awarded custody of another of her children (in a decision that was mercifully reversed).

It is a pattern we saw last year, when Delaware prosecutors -- after blustering about first-degree murder charges -- settled for manslaughter pleas and less than three years each from two Delaware teenagers who killed their baby. It is as though these babies are something less than real people and killing them is something less than real murder. It is an attitude that the courts and the culture reinforce in one another, and that has to change.