Human Rights Watch (HRW) and Columbia Law School’s Prevention of Crimes Against Humanity Project on Monday released a report promoting the adoption of a treaty on crimes against humanity, to ensure effective prosecution of the most serious crimes.

According to HRW, “momentum builds” for the Convention on the Prevention and Punishment of Crimes Against Humanity. The planned treaty would refine the 2019 International Law Commission (ILC) draft articles on crimes against humanity. Twenty-five recommendations have been proposed for UN delegations to consider before negotiations. In particular, proposed amendments protect historically marginalized groups, such as “Indigenous communities, women, children, people with disabilities, LGBTQ people, and survivors of crimes against humanity,” and allow member states to meaningfully advance avenues for redress. The report states that a new treaty may be adopted as soon as 2029.

The new treaty would deal with crimes against humanity exclusively and would allow for uniform treatment of such crimes within various international jurisdictions. HRW said that “the treaty could anchor justice for crimes against humanity more solidly in international law, spurring states to adopt national laws and bolstering the efforts of domestic courts through mutual legal assistance.”

The report outlined how certain treaty definitions should be refined, particularly to recognize “the unique harms faced by women, people with disabilities, children, and other groups.” In one example, experts argued for more express language to cover the crime of forced marriage. Currently, forced marriage is prosecuted under a catchall category found in Article 7(1)(k) of the Rome Statute. Correlative with the proposal, in 2022 an International Criminal Court (ICC) Appeals Chamber held that the crime differed from the other crimes against humanity because of its unique character: a coercive union that violates a person’s right to consensually choose a spouse and start a family.

The report also argued for greater accessibility in amendment discussions. For example, webcast proceedings with simultaneous translations are recommended to allow various groups to participate. These groups include “victims’ and survivors’ groups, women’s rights defenders, Indigenous communities, academics, people with disabilities…children and young people.”

Crimes against humanity are serious crimes that are committed as part of a widespread or systematic attack directed against a civilian population. Among these crimes are murder, extermination, enslavement, torture, rape, forced pregnancy, persecution, enforced disappearance, and apartheid.

While the potential treaty would further formalize such crimes, HRW acknowledged that the prohibition of crimes against humanity has long been an established peremptory norm, which has also been confirmed by the ILC. Moreover, crimes against humanity are codified in the Rome Statute.

UN member states decided to start formal work on the new convention in December 2024. Formal negotiations were discussed at a meeting in the General Assembly Sixth Committee in October.