ACC staff are receiving financial incentives to kick long-term claimants off the corporation's books official documents show, the Green Party says.
But while ACC Minister Judith Collins has acknowledged staff motivated to move some claimants back into work, that was "a good thing.''.
Green ACC spokesman Kevin Hague said documents released under the Official Information Act showed ACC staff working with people receiving long-term claim payments had specific targets they had to achieve.
"Those same workers' remuneration is tied to achieving these targets.''
Mr Hague said it was "completely unacceptable that one of the performance mechanisms for ACC staff receiving pay is how many claimants are cut off from receiving their entitlements''.
"Incentivising the withdrawal of financial support for claimants will inevitably lead to this occurring before it is clinically appropriate in some cases.''
"It is also important to note that staff failing to meet ACC's self-imposed targets to move claimants off ACC may be penalised financially.''
But ACC Minister Judith Collins said while meeting targets for long-term claimants was part of the performance criteria case managers' pay was linked to, it was only one part.
"It's part of their framework but if they do well in the rest of their framework then that shouldn't affect their remuneration.''
ACC managers had told her that performance against the long-term claimant number targets, "doesn't necessarily mean a bonus or a drop in pay''.
Ms Collins said measures that helped case managers encourage people back into work where appropriate were a good thing.
"I don't see any problem with that, but where I do see a problems is if anyone's being forced off ACC when they're simply not able to work and I think that's a different thing all together.''