Tory MP Bob Neill's letter to the Metropolitan Police contains no evidence that the law may have been broken in seats other than Falkirk.
It would give greater legitimacy to Labour funding and force trade unions to make a positive case for supporting the party.
The Labour leader has to look like the head of a movement when he takes on Unite, not a lone crusader.
The growing strength of the Tory right and the anti-austerity left suggests our stable, predictable system of party politics may be coming to an end.
Many opposition MPs are persuaded by the case for making a virtue of necessity: resolve the issue and expose Tory divisions.
Desperate attempts to present Falkirk as part of a pattern of union abuse are as predictable as they are risible.
The six Labour MPs who voted in favour of Tory MP James Wharton's EU referendum bill.
If the allegation that the union signed up members to Labour without their knowledge or consent is proven, it could be charged with fraud.
The Labour leader must use this moment to emancipate himself from the machine that won him the job in the first place.
Shadow minister Ian Austin's dramatic call for an in/out referendum next year shows how party unity is fraying.