Abney’s injury in the attack prompted an FBI investigation that was ultimately abandoned.
Chea Vichea was a powerful labor leader able to amass large rallies, his killers have never been brought to justice.
At least 20 people, including some police and military police were injured, and at least 12 people were arrested.
Thailand forcibly returned more than 100,000 Cambodians last year.
Chhoung Chu Ngy briefly disappeared on Thursday last week, but he appeared shaken before a press conference on Friday.
The draft law has come under continued criticism from international and local NGOs, who say it will stymie their work.
The 19-year-old defrocked monk told VOA Khmer that he had startled a cleaning woman at his pagoda in Soc Trang province.
Chan Cheng and a party lawyer are accused of helping a party activist, Meas Peng, wanted for questioning in a land dispute.
Only 8 percent of commune councilors were women in 2002, compared to 15 percent after the 2007 elections.
The Ministry of Interior recently completed another draft of the law after it rejected the first version under international criticism.
Civil society leaders have said they would need at least a month to properly review the law.
The first version was sent back to them from the Council of Minsters, following widespread criticism from the international community.