Assizes na Ariano wasu jerin dokoki ne na Masarautar Sicily da aka ƙaddamar a lokacin rani na 1140 a Ariano, kusa da Benevento, na Roger II na Sicily. Bayan kwanciyar hankali a kwanan nan, a cikin tawaye, ya yanke shawarar yin ƙaura zuwa gwamnatin da ke tsakiyar. Assizes sun kafa babban ofisoshin Sicilian kuma sun nemi kiyaye tsarin mulkin a ƙarƙashin tsananin ikon sarauta. Ya ƙunshi maganganu arba'in waɗanda suka shafi dukkan batutuwan da suka shafi damuwar shari'a ta zamani: kadarorin masu zaman kansu, kadarorin jama'a, coci, dokar farar hula, kuɗin masarauta, da sojoji. Aikin ya ci gaba don zamaninsa, yana samun ƙa'idodinsa ba daga Norman da Faransanci kaɗai ba, har ma da Muslim da Byzantine (musamman Justinian ) ra'ayoyin shari'a. Rabin farko na 1140 Roger ya kashe a Palermo yana shirya Assizes. Tabbas an shirya su sosai. Duk da rubuta dokar a babban birninshi, a watan yuli, ya yi tafiya a cikin jihar zuwa Salerno, babban birni na masarautar Apulia, daga nan kuma ya tafi Abruzzi, inda ya bincika cin nasarar ɗiyansa: Roger da Alfonso .