"Israel is correct that identifying combatants in a heavily populated area is difficult, and that Hamas fighters at times mixed and mingled with civilians," Richard Goldstone wrote in an op-ed for The New York Times published on Thursday. "But that reality did not lift Israel's obligation to take all feasible measures to minimize harm to civilians." The South African judge, who was the chief prosecutor for war-crime tribunals on Rwanda and the former Yugoslavia, headed the UN commission investigating Operation Cast Lead, which released a scathing report on Tuesday accusing Israel of war crimes, resulting in Jerusalem attempting to undermine the validity of the report. "In armed conflict civilians should to the greatest extent possible be protected from harm," Goldstone wrote. "In the fighting in Gaza, all sides flouted that fundamental principle." "In Israel, three civilians were killed and hundreds wounded by rockets from Gaza fired by Hamas and other groupsâ€¦ In Gaza, hundreds of civilians diedâ€¦ Repeatedly, the Israel Defense Forces failed to adequately distinguish between combatants and civilians, as the laws of war strictly require," Goldstone continued. But while noting Hamas's declared intention of killing Israeli non-combatants, Goldstone did not hesitate to draw a parallel between the Islamic group and Israel, which he acknowledges has been investigating its military while casting doubt upon the validity of such probes. "Unfortunately, both Israel and Hamas have dismal records of investigating their own forces," Goldstone wrote. "I am unaware of any case where a Hamas fighter was punished for deliberately shooting a rocket into a civilian area in Israel - on the contrary, Hamas leaders repeatedly praise such acts. While Israel has begun investigations into alleged violations by its forces in the Gaza conflict, they are unlikely to be serious and objective." The need for an external investigation follows, he said. "If justice for civilian victims cannot be obtained through local authorities, then foreign governments must act," Goldstone maintained, and can pursue justice through such bodies as the International Criminal Court. "Abusive fighters and their commanders can face justice, even if their government or ruling authority is not willing to take that step." Goldstone said he does not ignore the "challenge" in the fact that "Western governmentsâ€¦ [that pushed] for accountability in places like Darfur," must "now must do the same with Israel, an ally and a democratic state," since "failing to pursue justice for serious violations during the fighting will have a deeply corrosive effect on international justice, and reveal an unacceptable hypocrisy."