The legitimacy of military commissions trying opposing combatants had been established during the Mexican War.
ðə lədʒˈɪɾɪməsi ʌv mˈɪlətˌɛɹi kəmˈɪʃənz tɹˈaɪɪŋ əpˈoʊzɪŋ kˈɑːmbætənts hɐdbɪn ɪstˈæblɪʃt dˈʊɹɹɪŋ ðə mˈɛksɪkən wˈɔːɹ.