Robert Peston: Will the Boardman inquiry save or sink David Cameron?

The government inquiry sparked by the furore over David Cameron's lobbying on behalf of Greensill is expected to have three "buckets", according to sources.

First bucket: should lobbying rules be changed to prevent former prime ministers exploiting their privileged access to serving ministers and officials on behalf of commercial clients?

Second bucket: is it appropriate or useful for government to use "supply chain finance", of the sort provided by Greensill to speed up payments to pharmacists and NHS employees - in essence, are there hidden or unnecessary costs for the public sector?

Third: were rules broken - was their wrong doing - by government ministers and officials when engaging with Cameron and Greensill in deals done and in deals rejected?

The review will be carried out by the leading corporate lawyer Nigel Boardman. He has not yet established how deep each of his buckets will be (that is, how much information to trawl), how long he will need and whether he will publish a report on his findings.

As I understand it, however, his presumption is that there will be a report. What I am less clear about is the underlying motivation of the prime minister and Whitehall mandarins in establishing the Boardman review.

Is it a classic government exercise in obfuscation - an attempt to protect a recent Tory prime minister, David Cameron, by ordering a review that will look at what's wrong with the system rather than at individual culpability?

Or should Cameron be anxious that after decades of rivalry with Johnson, his successor as PM sees an opportunity to apply the coup de grace?

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