ONE OF the worst blots on Virginia’s history is the decades-long, state-sponsored barbarity known as eugenics — the effort to forge a scientifically enhanced race purified of what some considered inferior genetic stock. Former governor (now Sen.) Mark Warner acknowledged the disgrace that led to the forcible sterilization of some 7,000 people deemed feebleminded, epileptic or in some other way unfit to have children.

Given that appalling past — which Virginia stuck with until the 1970s, decades longer than most other states — it would be logical to think the state would, once and for all, be done with the business of determining who is fit for parenthood.

Apparently, word failed to reach Shenandoah County, where prosecutors last month struck a plea deal with a man who agreed to undergo a vasectomy in return for a shorter prison sentence.

Jessie Lee Herald, the 27-year-old defendant, has a criminal past that includes guilty pleas and convictions for cocaine possession, hit-and-run and beating up another man. In his latest brush with the law, he pleaded guilty to child endangerment, hit-and-run and driving on a suspended license.

The prosecutor who handled the case, Ilona White, seemed particularly concerned that Mr. Herald has had seven children with six women, including a 3-year-old with his current wife. In return for dropping some charges, she offered a measure of leniency if Mr. Herald assented to the operation once he leaves prison after serving a four-year term. Thus coerced, Mr. Herald reluctantly agreed.

This is outrageous. Mr. Herald is not a sex offender, nor is there a shred of evidence that his criminal behavior derives from the fact that he has fathered seven children. In the hit-and-run to which he pleaded guilty, he did flee with his 3-year-old, who sustained minor injuries and was found by authorities later that day with glass in his diapers.

That may be evidence of negligence — hence the charge of child endangerment — but it does not justify depriving Mr. Herald of the ability to father future children. His wife, who wants to have more children with Mr. Herald, said he is a good husband and father.

Even if he weren’t, by what right does the state of Virginia wield the power to determine who may have children? Mr. Herald accepted the deal “voluntarily” but only because of the state’s coercion; Mr. Herald was eager to reduce his prison term.

As Steve Benjamin, a prominent Virginia defense attorney, pointed out, the point of punishing criminals is to deter future criminality. But fathering children is not illegal; it is a fundamental human right.

As for the prosecutors, they seem to have been motivated more by offended sensibilities than by addressing crime and protecting the public. After reviewing the case, said Ms. White, the prosecutor, vasectomizing Mr. Herald “really did seem like it would be in the best interest of the Commonwealth.”

Really? Where exactly does she draw that line? One wonders what other criminal defendants will be similarly judged, and surgically altered, in Shenandoah County.