The Otago Regional Council has refused to publicly back offshore oil and gas exploration after being told it would be illegal to take a stance.
Texan company Anadarko is about to begin drilling its first test well off the Otago-Southland coast in the search for a possible gas field.
At the council's meeting on Wednesday, councillor Gerry Eckhoff put forward a motion to support the exploration programmes, but most councillors refused to debate it and voted it down.
The regional council's lawyer had warned that taking a public position would be illegal under changes to the Local Government Act and could prejudice future resource management decisions.
Mr Eckhoff called that advice "stunningly bad" and said it was an instance of muzzling representative democracy.
"Because this debate has not taken place as it should've, I think many voters, many people of this region will feel totally disenfranchised that their representatives have chosen not to speak on this important matter on their behalf."
Mr Eckhoff said he would be seeking a judicial review of the council's decision.