During her first big public outing as leader during the election, she promised rail for all – including a line from the Auckland waterfront to Dominion Rd to Mount Roskill, all to be completed by 2021.

The promise was part of a $15 billion package and came with a plea from Ms Ardern – she needed cash to fund it.

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“You can call a regional fuel tax ‘crowd-sourcing’ if you like,” she told the public.

That part of the promise did come true: Aucklanders are paying the 10 cents a litre more at the pump.

But Labour hasn’t done the rail part.

On Wednesday, Transport Minister Phil Twyford admitted the Government would fail to build light rail down Dominion Rd by 2021. Instead, he only expects work to start on it next year.

However the Government isn’t counting it as a broken promise.

Mr Twyford’s defence is that promises made by Jacinda Ardern as Labour leader are completely different from promises made by Jacinda Ardern as Prime Minister.

It’s a convenient excuse for a broken promise.

Newshub.