American soldiers and Marines in Iraq are convicted of the homicides of noncombatants but sentenced to no confinement; no officer is held accountable for abuses at Abu Ghraib prison. These are just two disturbing military legal headlines.

Why are court-martial convictions seemingly hard to come by? The homicides of 24 Haditha civilians, including women and children, for example, resulted in court-martial charges against eight Marines, including four officers. Almost two years later, however, charges have been dropped against — so far — two of the four alleged shooters and one of the four officers.

Is the military justice system broken? Has the Uniform Code of Military Justice, the military's criminal code, failed? Does the United States pay lip service to the law of war while disregarding it in fact?

First, remember that war crime charges involve very few of the many thousands of heroic U.S. war fighters in Iraq and Afghanistan, and also that being charged does not necessarily mean one is guilty. The Uniform Code of Military Justice has proved itself in peace and combat, including in Iraq and Afghanistan. But, undeniably, there are problems in prosecuting war crimes.

Although the code works well, the law of war — the part of international law that regulates armed hostilities — does not. The wonder is that it works at all. Some war crimes go unreported. That was particularly true in the early stages of the Iraq conflict. After the Abu Ghraib scandal, greater attention is given to enforcing the law of war, which partly explains the greater number of media accounts of criminality. Our military is not riddled with criminals. Rather, commanders are paying closer attention to possible war crimes and, as required by military law, they are investigating and reporting them.

In Haditha, after an improvised explosive device killed a popular Marine, 24 Iraqi noncombatants were killed. The Marine battalion commander denied the possibility of his men's criminality and failed to make sufficient inquiry into their actions, multiple investigations allege. Time magazine backed this up, and Marine headquarters cast a wide net in charging those possibly involved, including senior officers who may have investigated inadequately. The division commander, a two-star general, has been punished administratively. But multiple-murder cases present difficult problems for prosecutors, be they civilian or military. At Camp Pendleton, Calif., Haditha prosecutors were hard-pressed; every judge advocate available was brought into service for the defense or prosecution for the preliminary hearings. Marine lawyers were brought in from across the country.

Mistakes were made. Why so many grants of immunity in the case, and did they let culpable participants walk? Why so many dropped charges? Should the process be allowed to work through to verdict? The actual Haditha trials, not yet commenced, may prove to be models of trial practice.

Another case that didn't go as well as it should have was the one concerning the Army's abuses at Abu Ghraib. Senior officers were punished administratively rather than court-martialed. When an officer, Army Lt. Col. Steven Jordan, was finally tried, he was acquitted of criminal responsibility for the abuse of Iraqi prisoners. But regardless of his guilt or innocence, his prosecution was inexperienced and poorly done.

This case illustrates another problem hindering military justice in all armed service branches. Inexperienced judge advocates, lacking the courtroom time to develop trial skills, are faced with complex cases and are opposed by civilian defense lawyers who know all the courtroom gambits. Military lawyers, often graduates of the best law schools, handle too few contested cases to learn the tricks of the trade.

Finally, juries — civilian or military — are unpredictable in their findings of guilt or innocence and in sentencing. Military juries, usually combat veterans, sometimes seem inclined to demand absolute proof rather than the legally required proof beyond a reasonable doubt; their sentences sometimes are not commensurate with the crimes. No judge advocate, experienced or novice, can anticipate or cure that. Acquittals and dropped charges are part of every legal system.

After a shaky start in Iraq, military justice is working. Three soldiers involved in the rape-murder-burning of a 14-year-old Iraqi girl were court-martialed and sentenced to 90, 100 and 110 years confinement. Problems remain, but find a system without problems. Over time, our military's courtroom record is good.

Gary Solis is a retired Marine Corps judge advocate and teaches the law of war at West Point and at Georgetown University Law Center. He wrote this commentary for the Los Angeles Times.