On 23 March 2010, he wrote a letter to LICRA explaining his views. In this letter he noted particularly the views of Christian Delorme before a parliamentary commission of the French Senate. He also cited the book "L'Islam dans les prisons" by Farhad Khosrokhavar, who confirmed the figure of 70 or 80% of "Muslims in prison" estimated in a survey commissioned by the Ministry of Justice. The editors of "L'Express" noted that Farhad Khosrokhavar estimated the share of Muslim prisoners in certain prisons near so-called sensitive districts as between 50% and 80% and that there were no official national statistics on the subject.