HOW MANY TIMES can convicted Washington area sniper John Allen Muhammad be executed? Mr. Muhammad has been sentenced to death in a Prince William County court for the killing of Dean H. Meyers -- one of the murders that terrorized the D.C. area in 2002. Now, however, Fairfax County Commonwealth's Attorney Robert F. Horan Jr. has announced that he will bring Mr. Muhammad to trial on a second capital indictment for the killing in his jurisdiction of Linda Franklin. Meanwhile, Montgomery County State's Attorney Douglas Gansler has charged Mr. Muhammad with capital murder, and prosecutors in Alabama and Louisiana are seeking to put him to death in their states as well. All of which represents a potentially substantial waste of resources.

A second trial will be expensive, a third or fourth more so. The first trials of Mr. Muhammad and Lee Boyd Malvo cost nearly $3 million. Witnesses will be forced to relive horrible events again, courts to spend hundreds of hours trying redundant cases. What exactly is the point?

Mr. Horan has described this second case as an insurance policy against any problems the first death sentence or conviction might run into on appeal. And there are tricky legal issues in that case: the application of a previously unused state counterterrorism law and the question of whether Mr. Muhammad, who appears not to have been the triggerman, nonetheless satisfies a state law requirement that only immediate perpetrators of murders are eligible for death. Yet these same problems could affect any Fairfax case, so it's not clear how much insurance a second conviction would buy.

Some relatives might find some peace of mind in seeing the snipers tried, convicted and sentenced for killing their loved ones, rather than allowing some other victim's death to serve as a proxy for all of the killings. But solicitude for the relatives should not carry the day here. Timothy McVeigh was never tried for each of the 168 deaths in the Oklahoma City bombing case; the federal conviction for only a few of those deaths was allowed to stand for them all. Oklahoma retried Mr. McVeigh's accomplice, Terry Lynn Nichols, only when the federal case against him failed to yield a death sentence. That seems an appropriate way to proceed here. We oppose the death penalty even for Mr. Muhammad, but clearly many local residents will not feel that justice has been done if he is not eventually executed. His case, however, should not turn into an exercise of seeing how many times he can be sentenced to that fate.