His troubles may pale in comparison to those of Dominique Strauss-Kahn, but it will have been another difficult morning for Chris Huhne. The Labour MP Simon Danzuck has lodged a formal complaint with the Essex police force and an investigation seems certain to follow.
For now, Huhne remains in the cabinet and has pledged to fight the allegations but many feel that a leave of absence is the only appropriate response. As today's Telegraph notes, Peter Hain stood down as work and pensions secretary in 2008 while police investigated claims that he failed to report £100,000 in party donations.
For Nick Clegg, Huhne's woes are the first piece of political luck he has enjoyed since the formation of the coalition. In recent weeks the former SDP member had positioned himself as the natural successor to Clegg, talking up the possibility of a "progressive alliance" and emerging as the leading critic of the No to AV campaign.
That Huhne won more votes than Clegg in the 2007 Lib Dem leadership election (1,300 votes were delayed in the Christmas post and never counted) meant that he had an honourable claim to the leadership. But with his political woes, there is now no obvious replacement for Clegg in the cabinet. Vince Cable, by his own admission, is too old, and neither Danny Alexander (a man tainted by his association with George Osborne) nor Michael Moore shows any sign of leadership ambition.
The obvious replacement for Clegg is the party president, Tim Farron, but he, sensibly enough, is keeping his powder dry until 2015.
In the meantime, we can expect speculation over Huhne's possible replacement to grow. The coalition agreement guarantees the Lib Dems at least five seats in the cabinet. The severe penalty handed down to David Laws (the Commons will vote this afternoon to suspend him from the House for seven days) means that his name is not in the frame. But, for everyone else, the jockeying begins now.