A political commentator says it's telling only one person's been held accountable after multiple leaks from the public service.

Casey Costello had to apologise in the House this week, after claiming she hadn't sought advice on freezing tobacco excise tax, despite notes leaked to RNZ showing she did.

The Health Ministry's confirmed the person responsible for the leak is no longer employed.

Former MP Peter Dunne says this isn't the only leak there's since the Government's formed.

"It just makes me wonder whether they found someone who's being a bit of a scapegoat for all of the leaks, even if they're not responsible for them."

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