Going back to the days when the SDP conspired to make him the MP for Darlington, Michael Fallon is well-remembered in the North East as obnoxious to the point of insufferability.
On this morning's Today programme, he repeated, but outside parliamentary privilege, David Cameron's defamation of Suliman Gani.
An action before the civil courts could easily be crowdsourced, if necessary.
But Sadiq Khan is a solicitor. Over to him.