There's widespread uncertainty among developers after a Department of Conservation wildlife permit was deemed unlawful. 

The High Court in Wellington made the decision over the Transport Agency having permission to inadvertently kill protected wildlife at the Mt Messenger project site. 

The decision broadly means nothing can be killed unless it has a disease, there is overpopulation - or something similar. 

Simpson Grierson partner Sally McKechnie says some permits may now be invalid. 

"It's a case by case basis that will depend on the given permit - but we've got clients, we know we've got colleague firms around town that have clients trying to work exactly that out."

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