It is understood that Dettori is pleading guilty to taking a banned, non-performance-enhancing substance, believed to be cocaine, causing him to return a positive test at Longchamp in September.
The British-based Italian is likely to receive a six-month international ban, but hopes that France Galop will backdate the suspension to his last appearance, at the Melbourne Cup on 6 November.
That would allow Dettori, the face of flat racing for the last 20 years, to return to action in time to compete in the Oaks at Epsom on 31 May and the Derby at the same venue the following day.
France Galop is not expected to announce its verdict until tomorrow, while it is unlikely but possible that it could decline to backdate the suspension. A six-month ban enforced from this week would see Dettori miss the Oaks and Derby.
The 41-year-old, who is currently temporarily suspended while he awaits the verdict, will appear in person today in Paris. His positive test came on 16 September, a day of major trials for the Prix de l’Arc de Triomphe.
Dettori is intending to ride freelance on his return, having split from Godolphin in October, before his positive test came to light, after 18 years with the thoroughbred stable.
The three-time Champion Jockey is keen to add to his solitary Derby success, in 2007 aboard Authorized, and his trio of victories in the Oaks, which he won most recently with Kazzia in 2002. Perhaps his most famous achievement came at Ascot in 1996, when he rode all seven winners on Champion’s Day.
France Galop only has authority to ban Dettori from riding in its own territory, but other racing jurisdictions would almost certainly reciprocate the suspension.