• 1968 massacre at My Lai, Vietnam, led to controversial courts-martial of US soldiers
• What laws apply to warfare? How can they be enforced?

A nation's rules of warfare—what are they? How are they determined? How do they apply to soldiers and their commanders? What are these rules with respect to enemy combatants and enemy civilians? What sorts of penalties should be meted out to those who violate such rules? And who should decide how to answer these questions?

These were the issues facing the US military court that charged First Lieutenant William Calley with the premeditated murder of 22 Vietnamese civilians, including infants, children, women, and elderly men. Calley was also charged with assault with the intent to kill a toddler. All this carnage had occurred in the tiny village of My Lai during an American military search-and-destroy mission in the Republic of South Vietnam in 1968, at the height of the Vietnam War. The case against Calley (and, eventually, fourteen other military officers) emerged from the investigations conducted by Colonel William Wilson. To his horror, Wilson learned that the inconceivable rumors about the ruthless slaughter of My Lai villagers by US infantrymen under Calley's command were true. What's more, he found that such crimes during the Vietnam War were not only common but had become somewhat routine; because these assaults occurred under the watch and, as Wilson discovered, even under the orders of commanding officers, they went unpunished. "I wanted the bastards exposed for what they'd done," the Army colonel later remembered.⁴

In 1971, during just one of several nationally publicized court-martial trials, several witnesses—each of them active military personnel, many hesitant to testify for fear of retribution at the hands of the US Army—attested to the crimes facilitated and committed by First Lieutenant William Calley. One of the many witnesses was Herbert Carter, a soldier from Calley's company. In his emotional testimony to the judge and jury, Carter recalled that when one Vietnamese woman emerged from a hut holding her wounded child, a fellow soldier shot her and then the baby. "There was no reason for this killing," Carter concluded. "It was murder." ⁵

Later, Calley took the stand in his own defense. When asked to explain his decision to gun down whole groups of non-combatants—young, old, male, and female—Lieutenant Calley stated, "I was ordered to go in there and destroy the enemy.… That was my job on that day. That was the mission I was given. I did not sit down and think in terms of men, women, and children."⁶ He spoke not of civilians and admitted to no errors of judgment; he said only that he had been following orders from his superiors. In Calley's mind, in a war of counterinsurgency in which his men faced constant surprise attack by guerrilla fighters, there could be no meaningful distinction between enemy combatants and civilians.

The jury, made up entirely of commissioned military officers, deliberated for thirteen days. Ultimately, it refused to accept Lieutenant Calley's defense and found him guilty for each of the twenty-two murders and for ordering the killings of many more. Head jurist Clifford Ford, a colonel, announced that Calley would be "confined at hard labor for the length of your natural life; to be dismissed from the [military] service; to forfeit all pay and allowances."

Just three days after Calley's sentencing, President Richard Nixon stepped in; he ordered the convicted war criminal dismissed from hard labor, removed from his prison, and placed under house arrest (a nice alternative to jail, to say the least). Furthermore, the president vowed to review the details of Calley's case and assist him in seeking an appeal. In response, Captain Aubrey Daniel, the prosecuting attorney in the case, penned an angry letter to the White House. "I would expect," he scolded, "that the President of the United States, a man whom I believed should and would provide the moral leadership for this nation, would stand fully behind the law of this land on a moral issue which is so clear and about which there can be no compromise."⁷

Despite protest from Daniels, legal professionals, military officials, and both Vietnamese and American citizens, the Military Court of Appeals agreed to hear the case. In 1973, the Court upheld Calley's conviction but reduced his sentence significantly to ten years. Still under house arrest, Calley petitioned the federal District Court for a review of the original court-martial proceedings. This time, the Court ruled that the trial had been unfairly conducted and marred by national publicity of the events. With one final confirmation from the Fifth Circuit Court of Appeals, Calley was freed, released after serving just three and one half years for his crimes.

Many Americans objected to what seemed a process tainted with favoritism and political posturing. They were angry that so many, including top officials and several admitted perpetrators, escaped unpunished. Still, others argued that Calley and the others sentenced for war crimes in Vietnam had been mere scapegoats for broader military misconduct, or that the conditions of the war itself were so horrific that no American soldiers ought to be prosecuted for anything they did in the heat of battle.

And many questions remained: how does the United States define war crimes? How should these offenses be prosecuted, and what are the appropriate consequences? Should national security factor into conviction or sentencing? What role should the president, in his role as Commander in Chief, play in wartime courts-martial? As we see from the case against Lt. Calley, the answers to these questions are not clear-cut. In fact, each of the My Lai cases proves that wartime circumstances, public opinion, and politics can influence—or even determine—the scope of the codes of war and the severity of punishments for offenses.