Justifier belong to the 1
st group. Justifier is a common french verb.
Justifier is conjugated the same way that verbs that end in :
-ier
Justifier is conjugated with
auxiliary avoir.
Justifier verb is
direct transitive, indirect transitive.
French verb justifier can be conjugated in the reflexive form:
Se justifier
Justifier verb is a direct transitive verb, so passive voice can be used.