Not since his embarrassing memory loss regarding the number of Tranz Rail shares he had or had not owned has the Prime Minister looked quite so uncomfortable as he did at his weekly press conference yesterday.

Neither has he sounded so unconvincing as he did in countering Labour accusations he misled Parliament a week ago when answering questions about the downgrading of New Zealand's credit rating by Standard & Poor's.

While John Key was saying one thing, his body language seemed to be saying something else.

He was bombarded with questions from journalists after the credit ratings agency issued a point-blank denial of his claim that it had privately warned a month or so ago that a downgrade was much more likely if there was a change of government after next month's election.


It now turns out his claim was based on second-hand information passed on to him in an email from someone who had been at a meeting between bank economists and representatives from Standard & Poor's.

Furthermore, the source - who Key refused to name - told him he was basing that claim on an "inference" he had taken from what Standard & Poor's had told the meeting.

Key insists his informant is well-known to him, someone who is trustworthy and reliable and who has previously passed on information which turned out to be correct.

Key obviously saved the email as useful material to throw back at Labour when the Opposition came after him in Parliament last week after the ratings downgrade the previous Friday. His attempt to catch Labour out has instead caught him out.

The whole episode might seem rather trivial in the grand scheme of things. However, the result of the election will be determined by two things - whether Labour can erode the vast stocks of kudos and credibility Key has built up with voters and whether Labour can persuade voters it would be a better manager of New Zealand's economy.

On both fronts, Labour is struggling badly. Key's own goals on both fronts will at least give some encouragement.

For Key, they serve as a timely pre-campaign reminder of the dangers of winging it without strong evidence to back up what you are saying.

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