A UN warning that Israel’s bombardment of Lebanon may constitute war crimes has legal legs - but with the issue as much about politics as law prosecutions are unlikely anytime soon, analysts say.

With reports of at least 300, mostly non-combatant, deaths in Lebanon during several days of air and artillery strikes, Louise Arbor, the UN Commissioner for Human Rights, said that certain Israeli actions constituted "foreseeable and unacceptable targeting of civilians" – illegal under international law.

Daniel Machover, a London-based human rights lawyer involved in the attempted prosecution of Israeli personnel for alleged war crimes in the West Bank and Gaza, agreed that reports about the number of civilian deaths and the extent of damage to civilian areas mean that Ms Arbor has "a very, very strong point".

International law on war crimes raises the prospect that individuals can be held criminally liable for military action. As Ms Arbor pointed out, such liability is not restricted to the military, but extends to politicians who approve their operations.

"In principle a whole range of people from the Israeli Prime Minister, through senior generals down to air force or artillery gunners could be guilty of war crimes," Mr Machover said.

International law classes a wide range of activities under the umbrella of war crimes, but the current focus is Israel’s aerial bombardment of Lebanon, where reports of civilian deaths in recent days include a family killed in their car while attempting to escape an area under sustained Israeli attack.

International law prohibits armies from: "Intentionally launching an attack in the knowledge that such attack will cause incidental loss of life or injury to civilians or damage to civilian objects…which would be clearly excessive in relation to the concrete and direct overall military advantage anticipated."

Professor Iain Scobbie, a member of the law faculty at London’s School of Oriental and African Studies, said that international law would allow individual Israelis to be held liable, if proven, for breaching these requirements.

Israeli Government representatives insist that all air strikes are subject to proper assessments and commanders are ordered to abort attacks that are deemed to carry unacceptable civilian risks. There is also the possibility that civilians could be killed as a result of stray Hezbollah rockets or gunfire.

Mr Machover said that in order for a war crimes prosecution to be initiated, very detailed investigations into exactly which targets were hit, when and by whom would be needed. If there is sufficient evidence then independent military experts can be called to give opinions on whether the attacks were justified.

Aside from the difficulty of collecting reliable evidence from a war zone, Mr Machover warned of the ever-present political dimension in war crimes cases.

Israel has not ratified the Treaty of Rome, which limits the scope for war crimes prosecutions against its soldiers, but two options remain. The United Nations can convene an ad-hoc war crimes tribunal, as it did to try Slobodan Milosovic, but is very unlikely to do so long as America continues to support Israel’s military action in Lebanon and holds a UN veto, according to Mr Machover.

This leaves scope for individual countries to bring war crimes prosecutions in their national courts under their own laws. But with senior Israeli generals and politicians wary of traveling to certain countries and extradition unheard of, this remains a highly unlikely prospect.

With war crimes accusations flying at Israel, lawyers point out that Hezbollah, the Lebanese group whose kidnapping of two Israeli soldiers precipitated the current crisis, is not exempt from international law and so not immune to prosecutions.

The legal rules are more complex, and prosecutions even less likely, but Hezbollah’s kidnappings and rocket attacks put it in breach of both The Geneva Convention and its subsequent amendments. Another possibility, albeit extremely unlikely, are straightforward homicide charges against Hezbollah leaders.

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