The work towards a Treaty on Mutual Legal Assistance in Criminal Matters (MLAT) was initially explored by Malaysia at the 8th ASLOM held on 15 – 16 June 2002 in Bangkok, Thailand. The proposal aimed to support and strengthen ASEAN Member States’ effort and capacity to combat transnational crimes and other transnational challenges by enhancing cooperation in law enforcement and mutual legal assistance in criminal matters. It was also in response to the need to improve the effectiveness of judicial assistance and to regularise and facilitate mutual legal assistance’s process in view of ASEAN Member States’ different legal systems and procedural requirements. 

Subsequently, Malaysia initiated and hosted the meetings of like-minded ASEAN Member States to formulate the MLAT that leads to its conclusions on 29 November 2004 in Kuala Lumpur, Malaysia. Myanmar and Thailand became Signatory’s States to the MLAT in 2006. The MLAT entered into force in 2013 following the completion of all necessary internal legal procedures of ASEAN Member States for its entry into force.

Following the MLAT’s entry into force, further discussions and considerations to upgrade the MLAT were initiated. It was successfully completed as an ASEAN Treaty and was endorsed during the 6th Meeting of the Attorneys-General/Ministers of Justice and Minister of Law on Mutual Legal Assistance in Criminal Matters (6th AG MLAT) on 25 April 2019 in Yogyakarta, Indonesia. The 6th AG MLAT also endorsed the “Senior Officials’ Meeting of the Central Authorities on Mutual Legal Assistance in Criminal Matters” (“SOM-MLAT”) and “ASEAN Ministers/Attorneys-General Meeting of the Central Authorities in Mutual Legal Assistance in Criminal Matters” (“AMAG-MLAT”). Both the AMAG-MLAT and its SOM-MLAT have now been included as ASEAN Sectoral Ministerial Body in Annex 1 of the ASEAN Charter under the ASEAN Political-Security Community pillar.