Singaporean Prime Minister Lee Hsien Loong urged Asean member states to begin drafting a regional extradition treaty, prompting observers to raise concerns over the existing misuse of expatriation procedures by countries in the 10-member bloc, including Cambodia.

The comments were made in the Singaporean premier’s statement to the 32nd Asean Summit, attended by Prime Minister Hun Sen over the weekend. Lee said that a model extradition treaty had already been agreed upon by all members and that it was time to start work on an actionable draft.

“We noted that work could commence on an Asean extradition treaty as a next step, to strengthen Asean’s resilience and capacity to combat transnational crime, and to enhance cooperation within Asean to ensure respect for the rule of law,” his statement reads.

Cambodia has been criticised by rights groups for attempting to extradite political dissidents, especially from Thailand, which is often the first port of call for anyone escaping the country. The two countries already share an extradition treaty.

Sam Sokha, wanted for throwing a shoe at a ruling party billboard last year, was arrested in Thailand for overstaying her visa and sent back to Cambodia, despite being a UN-recognised refugee. She was then convicted by a Kampong Speu court and sentenced to two years in prison for “incitement to discriminate” and “insulting a public official”, a decision condemned by Human Rights Watch, Amnesty International and the UN Refugee Agency.

Last week, political dissident Sam Serey, branded a “terrorist” by the government, was also arrested in Bangkok for overstaying his visa, with Cambodian officials putting in a request for his extradition. Serey, however, was sent back to Denmark, where he has permanent residency after being granted political asylum.

Human Rights Watch’s Phil Robertson said probably only a few people had seen the text of the model Asean extradition treaty, given the bloc’s opaque operations and refusal to include civil society in decisions.

“But already alarm bells are going off because governments like Cambodia, Thailand, Singapore and others in the region obstinately refuse to understand that fear of political persecution is a legitimate reason to not extradite someone,” he said.

Paul Chambers, lecturer at the Naresuan University in Thailand, said it was likely any regional extradition treaty would benefit repressive regimes.

“Such a treaty could, however, help authoritarian regimes within ASEAN assist each other to deport exiled dissenters home to face state punishment,” he said via email.