[Analysis] Asser Institute researcher León Castellanos-Jankiewicz on Mexico’s request to intervene in the case against Israel for alleged genocide in Gaza  

Mexico has requested permission to intervene in the case against Israel at the International Court of Justice (ICJ) for alleged genocide in Gaza. This announcement was made by the court on Tuesday. Spanish newspaper El País asked Asser Institute researcher León Castellanos-Jankiewicz to comment on the development. ‘Mexico has a very clear legal interest as a signatory of this treaty’. 

The case was initially filed by South Africa in December last year, following Hamas’ October 7 terrorist attack and Israel’s military response in Gaza. Mexico, a signatory of the Convention for the Prevention and Punishment of the Crime of Genocide, aims to contribute its perspective on the interpretation of international law principles relevant to the case.  

The Mexican government has taken a step forward to say how, in its opinion, these principles should be interpreted in the context of the conflict in Gaza. The Convention is one of the most important legal instruments in the international system because it addresses basic humanitarian considerations. 

‘A clear legal interest’ 
León Castellanos-Jankiewicz, international law expert at the Asser Institute, explained in Spanish newspaper El País that Mexico's legal interest as a State party to the Genocide Convention motivates its intention to support the ICJ in determining its legal position. “Mexico is communicating to the Court its intention to share its views about the content and scope of the Convention on Genocide”, he said.  

The Mexican government has condemned civilian attacks in Palestinian territories while also opposing the terrorist attacks that triggered the conflict on October 7. In April, Mexico reaffirmed its commitment to a two-state solution that ensures Israel's security and establishes a viable Palestinian state. The recent discovery of Orión Hernández's body, a Mexican citizen kidnapped by Hamas, has added a personal dimension to Mexico’s involvement in the case.  

Following Mexico's request to intervene, Israel and South Africa must provide their written positions for the ICJ to consider. Castellanos-Jankiewicz: “The ICJ has a very clear procedure in its Statute and in the Rules of the Court: after a State asks to intervene in a case, the Court first consults the parties to the dispute to see what they think; these responses will be weighed by the ICJ and based on this analysis, the Court will inform Mexico whether it can intervene or not.”  

Other interventions 
Nicaragua and Colombia have also shown interest in intervening in the case, with Colombia making a similar request in April under Article 63 of the ICJ Statute. Libya made a formal request on May 10, and other countries, including Egypt, Ireland, Belgium, Maldives and Turkey, have shown interest, according to El País. 

On May 24, the ICJ issued provisional measures addressed to Israel, demanding an immediate halt of military offensives against Palestinian civilians in Rafah and requesting that Israel ensure that humanitarian aid corridors remain open. Recent bombings in Rafah by Israeli forces have resulted in significant civilian casualties and displacement, prompting warnings of a humanitarian catastrophe, and provoking anger by many European leaders.  

Read the full article (in Spanish).  

Read more 
In a new episode of JurisDictions, the Asser Institute international law podcast by researcher and podcast host Dr Carl Lewis, four guests discuss the ICJ’s South Africa v Israel case. The International Court of Justice (ICJ) has provided two orders of provisional measures in the Application of the Convention on the Prevention and Punishment of the Crime of Genocide in the Gaza Strip (South Africa v. Israel) case, following the further deterioration of the humanitarian situation in Gaza since the 26th of January 2024. But what are provisional measures? What does it mean to invoke a breach of an obligation owed to the ‘international community’? What implications follow from these proceedings beyond the Peace Palace? And in what sense could it be argued that the ICJ may be denying reality? Listen now.  

[Public lecture] The right to health for women in armed conflict: Addressing international law’s role in the humanitarian crisis in Gaza 
On June 6, the Asser Institute organises a free lecture on the right to health for women in conflict, addressing international law’s role in the humanitarian crisis in Gaza. According to a UN Report updated in February 2024, around 700,000 menstruating women and girls in Gaza have limited access to hygiene supplies. This scarcity, compounded by a lack of water has increased infections to an unprecedented rate. This lecture will explore states’ existing obligations under international humanitarian law (IHL) and international human rights law (IHRL) in relation to the right to health in conflict, specifically focusing on how these regimes intersect in the context of the conflict in Gaza. Register now.

Dr León Castellanos-Jankiewicz