The crackdowns have been widely condemned, but no perpetrators have been arrested or reprimanded.
Representatives of nine unions met together have made seven resolutions to seek better conditions and wages for workers in Cambodia’s factories.
Two women wounded in the 2011 protest shooting in Svay Rieng province have seen their conditions worsen.
At least four people were killed when police fired on demonstrators during the Jan. 3 crackdown, no one has been arrested or reprimanded in the wake of the shootings.
The protesters gathered in New York despite a cold snap that dropped temperatures and snow on the city.
Meanwhile, international buyers say they want improved conditions for workers, who should also be allowed to assembly and collectively bargain.
The group interviewed nearly 200 factory workers from 55 different factories, and found that anti-union discrimination and poor workers conditions were frequent.
In testimony before the UN Human Rights Council last week, Mak Sambath, vice chairman of Cambodia’s Human Rights Committee, denied government involvement in the tribunal.
Sam Rainsy, head of the Cambodia National Rescue Party, was this week in Geneva, where a UN human rights review of Cambodia took place.
About 100 riot police blocked demonstrators from submitting petitions to foreign embassies on Wednesday, though in a change from recent days, no violence or clashes ensued.
The review for more than 190 countries will be held from Jan. 27 to Feb. 7, Cambodia will present its report Tuesday afternoon.