They compared Dreyfus's handwriting to that on the memo and concluded that it was a match, even though outside professional handwriting experts were much less confident in the similarity, but never mind that.
Ils ont comparé l’écriture  de Dreyfus à celle du mémo et conclu que c'était la même. Les graphologues extérieurs étaient bien moins sûrs de la ressemblance mais peu importait.