More than 100 international law experts have released a statement alleging that US strikes on Iran over the past month constitute violations of the United Nations Charter and may amount to war crimes. The assessment comes after President Donald Trump threatened aggressive action against Iran during a recent public address.

Legal Concerns Raised by Experts

Just Security published a letter on Thursday, signed by a diverse group including senior professors, law association leaders, former government advisors, military law experts, and former judge advocates general. The experts argue that the US has violated international law since initiating military action alongside Israel on February 28th and in the conduct of the conflict since then.

“The initiation of the campaign was a clear violation of the United Nations Charter,” the experts stated, adding that “the conduct of United States forces since, as well as statements made by senior government officials, raise serious concerns about violations of international human rights law and international humanitarian law, including potential war crimes.”

UN Charter and Self-Defense

The UN Charter permits the use of military force only in self-defense against an imminent armed attack or when authorized by the UN Security Council. The experts emphasize that neither condition was met in this case. “The Security Council did not authorize the attack. Iran did not attack Israel or the United States,” they stated. They also found “no evidence that Iran posed an imminent threat that could ground a self-defense claim.”

Statements and Actions Under Scrutiny

The letter highlights concerning statements from administration officials. Defense Secretary Pete Hegseth reportedly described rules of military engagement as “stupid” and prioritized “maximum lethality, not tepid legality.” He also pledged “no quarter, no mercy for our enemies” in mid-March.

President Trump himself has stated he doesn’t ‘need international law’ and even suggested strikes against Iranian infrastructure were conducted “just for fun.”

Civilian Harm and Infrastructure Attacks

The experts cite widespread violations of the laws of armed conflict, including strikes against civilians, political leaders without military roles, and critical infrastructure. The UN’s high commissioner for human rights, Volker Türk, previously condemned these attacks for their “disastrous” impacts on civilians.

Data from the Iranian Red Crescent indicates at least 67,414 civilian sites have been struck, including 498 schools and 236 health facilities. The Human Rights Activists News Agency reports over 1,600 civilians have been killed since February 28th, including 244 children.

Specific Incident: Shajareh Tayyebeh School

The bombing of the Shajareh Tayyebeh Primary School in Minab on the first day of the war, which killed at least 175 people – most of whom were children aged 7-12 – is a particular focus. The experts believe this strike “likely violates international humanitarian law” and could be considered a war crime if recklessness is proven. They describe it as one of the deadliest attacks on civilians by the US military in recent decades.

Accountability and International Obligations

The experts warn that a lack of accountability has led to increasingly aggressive and reckless conduct. They also criticize the dismantling of internal safeguards meant to prevent violations of international law, including the removal of senior lawyers and the elimination of ‘civilian environment teams.’

While focusing on US actions, the letter also acknowledges illegal actions by Iran, including violent crackdowns on protesters and strikes on civilian areas in Israel and Gulf states. The experts urged US officials to uphold international law and reminded other nations of their legal obligations not to assist in internationally wrongful acts.

The signatories join a growing number of international law experts and human rights organizations condemning the war as illegal, including the UN, Human Rights Watch, Amnesty International, and Human Rights First. American University law professor Rebecca Hamilton expressed hope the letter would spur action from Congress, which she described as “flailing in the face of illegal actions by the executive.”