Usuli
They differ from their now much smaller rival Akhbari group in favoring the use of "ijtihad" ( i . e . , reasoning ) in the creation of new rules of "fiqh"; in assessing hadith to exclude traditions they believe unreliable; and in considering it obligatory to obey a "mujtahid" when seeking to determine Islamically correct behavior . 
<triplet> ijtihad <subj> fiqh <obj> part of <triplet> mujtahid <subj> fiqh <obj> part of