During this period he enjoyed a very large practice at the bar, being instructed in many causes célèbres including the Swynfen will case and Cardinal Newman's criminal prosecution for his libel of Giacinto Achilli.
The name derived from the French advocate François Gayot de Pitaval (1673–1743), wo published several volumes of causes célèbres et intéressantes between 1734 and 1743.
In criminal cases he drew public attention to himself by his cross-examination in the Bravo case in 1875, and from that time onward was connected with most criminal "causes célèbres," being conspicuous in the prosecution of fraudulent persons like Madame Rachel and Slade the medium.