The devastation caused by 50 days of fighting between Israel and Palestinian militant groups in the Gaza Strip a year ago was staggering.
On the Palestinian side, more than 2,000 people were killed, many of them civilians. Entire city blocks were reduced to rubble, and much of the electricity and water infrastructure was incapacitated. Panicked families described fleeing shelling in one neighborhood, only to encounter more blistering attacks in the next.
Israelis, too, were shaken by the conflict, especially in the south, where residents were pinned down in bomb shelters by rocket and mortar barrages from Gaza. The threat of an assault launched through secret tunnels leading into Israel was especially terrifying for many of them. Six civilians and 67 soldiers were killed on the Israeli side in the war.
But did any of this amount to war crimes? A series of investigations by the United Nations and human rights groups concluded that violations by the Israeli military and armed Palestinian groups could qualify as such.
Not so, say Israeli leaders who see in the reports evidence of bias against them. They contend that the country adheres to international law and went to unprecedented lengths to avoid harming civilians.
Hamas, the militant group that dominates the territory, has also taken issue with criticism of its conduct during the war, although it has welcomed the accusations against Israel. The West Bank-based Palestinian Authority, meanwhile, hopes the findings will bolster its case for charges to be brought against Israel at the International Criminal Court, which it joined this year. The court's chief prosecutor has opened a preliminary examination to determine whether events in Gaza and elsewhere merit a full investigation.
What are war crimes?
These are some of the gravest crimes in international law, so serious that the perpetrators can be prosecuted no matter how much time has elapsed. They involve breaches of the Geneva Convention and other violations of the laws and customs that apply in armed conflicts. Examples include the extrajudicial killing or ill treatment of civilians and prisoners of war; the wanton destruction of residential areas; and deliberate attacks on schools, hospitals or religious institutions.
What is the evidence against Israel?
Between July 7 and Aug. 26, 2014, Israeli forces carried out more than 6,000 airstrikes in Gaza, many of which hit residential buildings as families were sleeping or gathering to break their fast during the Muslim month of Ramadan. Densely populated areas were leveled by artillery and tank fire.
The number of civilians killed remains in dispute. A commission of inquiry appointed by the U.N. Human Rights Council concluded in June that 65% of the 2,251 Palestinian dead were civilians. Israel says it has documented militant activity by at least 890 of them.
Even when the U.N. panel was able to identify valid military objectives, it argued that in many cases the timing, weapons used and location of the targets suggest that Israel's attacks might have been disproportionate and therefore qualify as war crimes.
The finding was backed by soldiers' testimony collected by Breaking the Silence, an Israeli group, indicating that permissive rules of engagement and the use of indiscriminate fire contributed to the high civilian toll.
Israeli officials say they made repeated attempts to warn civilians of impending attacks, including leaflet drops, cellphone and text messages and so-called roof knocks, when smaller munitions were dropped on homes before the major strike. Many of the survivors, however, say they had insufficient time to escape, and no safe place to go.
In one case reviewed by the U.N. panel, a family was given just minutes to evacuate its home after a "roof knock" in the early hours, when its 22 members were asleep. Nineteen were killed.
In another case examined by the London-based rights group Amnesty International, the capture of an Israeli soldier on the outskirts of Rafah was met with a barrage of artillery fire and airstrikes that investigators said killed at least 135 people. (Israel says the number killed is lower.) The intense fire was intended to prevent the soldier's captors from moving him out of the area. But shelling continued for two days after Israeli authorities determined that he would not have survived the initial ambush, Amnesty said.
What is the evidence against Palestinian groups?
The U.N. report notes the "inherently indiscriminate nature" of the 4,881 rockets and 1,753 mortar rounds fired at Israel, which the panel said suggested that the purpose was to "spread terror among the civilian population, in violation of international humanitarian law."
Statements issued by some Palestinian groups indicated as much. Although others made attempts to direct their fire at military objectives, many of the weapons used by the groups did not have guidance systems and were launched in the direction of major population centers, including Jerusalem, Tel Aviv and Ashkelon.
The U.N. panel and Amnesty International also cited as possible war crimes the extrajudicial killings of at least 21 Palestinians accused of collaborating with Israel.
But no conclusions were reached about the tunnels built between Gaza and Israel. Although some had openings close to residential communities, they were used to conduct attacks only on military targets.
How have Israelis and Palestinians responded to the accusations?
Israel, like Hamas, did not cooperate with the U.N. inquiry. But Israel released its own report in June, arguing that military action was necessary to protect its civilians from attacks originating in Gaza. The report accuses Hamas and other groups of deliberately placing civilians in harm's way by firing rockets from inside and near hospitals, schools, mosques and homes, and by urging residents to ignore Israel's evacuation warnings.
"Israel does not commit war crimes," Prime Minister Benjamin Netanyahu said. "Israel defends itself from a terrorist organization that calls for its destruction and commits many war crimes."
The Israeli military has been looking into reports of misconduct and has referred at least seven cases for criminal investigation.
Palestinian authorities have pledged to do the same in Gaza. But Hamas rejects what its spokesman, Fawzi Barhoum, calls attempts to equate "the victim and executioner."
Human rights groups have faulted both sides for allowing impunity to prevail.