We can make trouble for you and we've done it to other people, Amrit Pal Singh was told, according to a recent Employment Relations Authority decision.
This included the threat of paying a woman $10,000 to make up a fake story that Singh raped her.
Singh was targeted by his ex-employer after he launched a complaint with the ERA in June 2014.
His visa conditions had restricted him to working at the Auckland bar, which has since changed hands.
But once the bar was sold to its current owner, Singh lodged his complaint against his former employer, claiming he was forced to work excessive hours for little pay.
Two months after lodging it, Singh was working at the bar when an intoxicated woman assaulted him and was subsequently arrested.
The next day, the woman's daughter visited the bar and asked Singh not to press charges against her mum, which he agreed to do.
Singh told his employer about the incident. But two weeks later, two people from his ex-employer's companies - and whose names cannot yet be published by court order - visited Singh at the bar.
One told Singh that "from day one he was not a good person and that he was stealing from them".
The second person said the incident with the drunk woman proved Singh was "not honest".
Saying they had experience making trouble for people, they threatened to track down the woman who assaulted Singh and pay her $10,000 to make a false rape claim.
They then whipped out a letter stating Singh was officially withdrawing his ERA complaint against the former employer.
Under these threats, Singh signed the letter.
One week later, one of the people asked Singh if he had sent the letter.
When Singh said he hadn't, the person stood over him in the bar until he typed and sent an email withdrawing his complaint.
One of the people involved was subsequently found guilty of blackmail in the Auckland District Court on March 29.
As a result of their conviction, the ERA - in a decision released this month - granted Singh permission to relodge his original complaint over his pay and work conditions.
"There is sufficient evidence to show that the applicant's withdrawal of his proceeding was procured through illegal means including threats unless he complied," the ERA decision said.
"There is also the fact that the [defendant was] convicted and sentenced for blackmail for the same actions."
This had led to "a miscarriage of justice", the decision said.
