Frankie Dettori faces a France Galop inquiry on Tuesday after testing positive for a banned substance at Longchamp in September.Kieren Fallon was banned six months by France Galop in 2006 after returning a positive test for a metabolite of a banned substance. France Galop then banned him a further 18 months after a second positive test in August 2007. Dettori himself was cautioned by police for possession of cocaine in 1993. Asked by the Daily Mail in 2010 about his biggest regret, he said: "Getting caught with cocaine in 1993. "I was on all the front pages and put my family through hell. I was cocky and had too much too soon. It made me grow up."