More than 100 international law experts based in the United States have signed an open letter condemning recent U.S. and Israeli military strikes on Iran as potential violations of the United Nations Charter and possibly amounting to ‘war crimes,’ according to Al Jazeera.

Unauthorized Attacks and Legal Concerns

The letter. Published on Thursday. Stated that the conduct of U.S. forces and statements by senior U.S. officials raise serious concerns about violations of international human rights law and international humanitarian law. The scholars warned that the U.S.-Israeli campaign, which began on February 28, was launched without UN Security Council authorization and without credible evidence of an imminent Iranian threat.

‘Force against another state is only permitted in self-defense against an actual or imminent armed attack or where authorized by the UN Security Council. The Security Council did not authorize the attack. Iran did not attack Israel or the United States,’ the letter said.

Concerns About Civilian Impact

The experts’ concerns fall into four areas: the legality of the decision to go to war; the conduct of hostilities; threatening rhetoric from senior officials; and what they describe as the dismantling of civilian protection structures inside the U.S. government under Defense Secretary Pete Hegseth’s ‘gloves off’ approach to warfare.

The scholars highlighted a strike on a primary school in Minab, Iran, on the first day of the war that killed at least 175 people, most of them children, as well as attacks on hospitals, water plants, and energy infrastructure. ‘We are seriously concerned about strikes that have hit schools, health facilities, and homes,’ the letter said.

Public Statements and Legal Disrespect

In particular, it noted a mid-March comment from Trump where he said the U.S. may conduct strikes on Iran ‘just for fun.’ It also cited comments from Pentagon chief Pete Hegseth from early March in which he said the U.S. does not fight with ‘stupid rules of engagement.’ The letter also condemned public statements by senior U.S. officials, including President Donald Trump.

‘Public statements by senior officials indicate an alarming disrespect for the rules of international humanitarian law accepted by states, and which protect both civilians and members of the armed forces,’ the letter said. It also added that the war is costing U.S. taxpayers up to $2bn a day.

The letter was co-authored by prominent legal scholars including Yale Law School’s Oona Hathaway and Harold Koh, Philip Alston of NYU, and former Human Rights Watch chief Kenneth Roth. The experts said that due to their connection to the U.S., their main focus was on the conduct of that government, but they ‘remain concerned about the risk of atrocities across the region.’

They also highlighted the ‘importance of equal application of international law to all, including countries that hold themselves out as global leaders,’ expressing concern about the harm this war is doing to the international legal order and the system of international law.

The signatories are urging Washington to change course, writing: ‘We urge U.S. government officials to uphold the UN Charter, international humanitarian law, and human rights law at all times, and to publicly make clear U.S. commitment to and respect for norms of international law.’