If Chris Huhne is charged then he’ll immediately leave the cabinet and there will be the most simple of government reshuffles.  The details of this were agreed between David Cameron and Nick Clegg as long ago as last summer, before the parliamentary recess.
I am not alone in saying the the favourite to replace Huhne as energy secretary would be Ed Davey, currently a parliamentary under-secretary at the business department.  This would be quite a leap for Davey – two rungs of government – but he fared badly when the Coalition was formed in 2010, having previously been the senior Lib Dem foreign affairs spokesman in opposition.

Other names mentioned as possibles to replace Huhne are the Foreign Office minister Jeremy Browne, and the former Chief Secretary David Laws.  Both men are very popular with Tory MPs, but that’s also a problem.  For their promotion would not go down well with many in the grass roots, who would not see it as the replacement of like with like.  Indeed, Laws and Browne are probably the two most right-wing MPs in the parliamentary Liberal Democrat party, while Huhne, in contrast, has always been seen as a man of the Left.  One senior Lib Dem I was speaking to recently compared Browne’s politics with that of John Redwood!  And he was only half-joking.

Another Lib Dem minister tipped for promotion is the Minister of State for Children Sarah Teather, who is very highly regarded by her boss in the Education Department, Michael Gove.  She has played an important conciliatory role in the often difficult relationship between Gove and Nick Clegg.  I don’t expect Teather to achieve promotion if Huhne has to quit, but she should be in the Cabinet before long.

Whoever takes over from Huhne, the favourite to come into government would be Tom Brake (like Davey, an MP from south west London), who was a front-bench spokesman for 13 years from 1997 to 2010.  Brake is reckoned by senior Lib Dems to have done a great job as co-chair of the party’s parliamentary home affairs committee, representing the views of Lib Dem MPs and peers to Home Office ministers.  Brake’s promotion would mean six of the party’s seven London MPs were ministers – the seventh being deputy leader Simon Hughes.

The Lib Dem backbenches are not over-brimming with talent right now.  I expect four or five ministers to lose their jobs when David Cameron initiates a large reshuffle later this year (including David Shutt in the Lords).  MPs in line for ministerial office, I reckon, are the husband-and-wife team Jo Swinson and Duncan Hames; as well as Jenny Willott, Stephen Gilbert and Don Foster.

Follow Michael on Twitter: @MichaelLCrick