Unfortunately, it now looks as if the worst has happened in the Dru Sjodin disappearance, and the state is building a strong case that its suspect is a murderer. (Many talk-radio callers to the contrary, there will be a trial to decide that.) Alfonso Rodriguez, having been a violent sex offender previously, the most important thing after putting him out of business once and for all will be to decide how we can best protect ourselves against other repeaters.

Forget the death penalty. In states with the death penalty, it is for murderers - and only a few of those - and would not have helped in the Sjodin case since his previous victims were not murdered. Also, of late the usual philosophical objections have been buttressed by an evolving DNA science demonstrating that, in the United States, we have put many innocent people on Death Row. Even old stalwarts such as conservative political columnist George Will have withdrawn their support.

The death penalty is not going to happen in North Dakota (or Minnesota either, most likely).

Probably, both North Dakota and Minnesota already have the best tool - civil confinement for those judged most likely to commit a sex crime. That law allows indefinite detainment of those who have done their time and even of those who missed a trial and probable conviction only because they were juveniles at the time of their offenses.

The concept has the approval of the U.S. Supreme Court, and the North Dakota law has passed muster with the state Supreme Court.

Minnesota failed to invoke civil confinement for Rodriguez, a fatal error of judgment, as it turns out. But that mistake does not invalidate the concept. You can bet Minnesota will be more careful next time.

Some will object to civil confinement as a radical departure from our usual way of doing things in this country. It is that. (Although we also use it for some mentally ill people and for out-of-control substance abusers.) But the very first civil right is the right of people to be safe in their persons, and the worst sexual offenders have demonstrated their utter pathological disregard for that. The one thing scarier than civil confinement is a society helpless to protect itself.

North Dakota has used its law sparingly over six years, subjecting only 11 people to it out of 1,300 registered sex offenders (180 of whom are thought to be high-risk). Multiple protections for the detained are built into it, including treatment - a condition insisted on by the state Supreme Court - the right to a state-paid attorney and state-paid expert, an annual review, and so forth.

In light of the Sjodin case, North Dakota is properly reviewing its various procedures for sexual offenders - including, says Gov. John Hoeven, the information it requires from other states whose offenders move here.

One feature that needs a good hard look is public notification. That one-time notice in the newspaper when an offender moves to town and maintenance of a Web site (www.ndsexoffender.com) are probably not enough.