One more low-ranking soldier was found guilty this week of abusing prisoners at the notorious Abu Ghraib prison in Iraq three years ago. Once again military brass supposedly in charge at the jail hunkered in their bunkers and let the enlisted forces take the heat.

Army Sgt. Michael J. Smith, 24, a security dog handler convicted of helping interrogations by setting his unmuzzled Belgian shepherd on selected detainees, was convicted on five counts of abuse. He could have been jailed for eight years, but instead was demoted, fined and sentenced to six months in the brig before being cut loose with a bad conduct discharge. Sgt. Smith's lawyers said the snapping-dog technique was approved by Abu Ghraib intelligence officer Col. Thomas Pappas, who was in turn instructed in such "enhanced interrogations" techniques by Maj. Gen. Geoffrey Miller. The next up the chain is Defense Secretary Donald Rumsfeld, who sent Gen. Miller to Iraq.

Col. Pappas was relieved of duty and reprimanded after the scandal broke two years ago. He testified he didn't know unmuzzled dogs were used to terrify prisoners under questioning. Gen. Miller was not called to testify.

Defendants in nine previous Iraq prisoner abuse trials failed to convince military judges that higher-ranking testimony is necessary. Army judge Col. James Pohl in earlier trials said top-echelon leaders had no bearing on the prison guards' conduct. Mid-level commanders like Col. Pappas have been reprimanded and demoted but spared military trials. Criminal charges of prisoner abuse in both Iraq and Afghanistan have gone no higher than a single Army captain sentenced to 45 days in jail and fined $12,000.

"A mere tap on the wrist for abusing prisoners gives the appearance that once again the United States is not serious about its responsibility to discipline those convicted of human rights violations," Amnesty International spokesman Curt Goering told The New York Times. Grunts who terrified and tortured prisoners in their care are going to jail themselves, at least for a little while. Their "superiors," those given responsibility for operations at Abu Ghraib, are protected from punishment by rank and the chain of command. A time-honored system meant to keep warriors accountable for one another's actions has failed.

These soldiers and their commanders -- right up to Secretary Rumsfeld -- betrayed the very principles they went to Iraq to uphold. Whether or not they do time, shame still blackens them and the good soldiers they represent.