The Council of Trade Unions is accusing the Government of always planning to water down new health and safety legislation.
The Health and Safety Reform Bill will not be reported back to Parliament until the end of July after Government MPs objected to what was in the legislation.
They particularly opposed clauses in the legislation they believed created too much red tape for small businesses and farmers.
Their revolt was given as the reason for delaying the Bill but it had already been substantially watered down before they objected.
For instance, businesses employing fewer than 20 workers were to be exempted from the requirement that firms have elected health and safety representatives with the power to stop work if they believed it was dangerous.
CTU president Helen Kelly said she did not believe the so-called backbench revolt was responsible for watering down the Bill because both Workplace Minister Michael Woodhouse and Prime Minister John Key supported weakening the legislation.
"It's a trick to try and divert from that very fact that they are intending to betray the miners killed in the Pike River Mine, the forest workers killed in New Zealand forests, the farmers being killed every day by watering down what are very, very essential provisions in the new law - a law that is based on the Australian model law where the accident rate is half the rate of New Zealand. Why wouldn't we just pass it?" Ms Kelly said.
She was particularly critical of the decision to not require small businesses to have elected health and safety representatives.
"Instead of promoting it as a positive thing for small business and encouraging your workers to pick up their rights and participate and get trained and all of those things, the Government's portraying it as red tape.
"And really it just reflects actually their attitude to working people in New Zealand that they're just a cost, they don't have any brains, they don't deserve any respect and they certainly don't deserve any rights."
Ms Kelly said elected health and safety representatives would actually help improve safety and take some of the pressure off small business employers.