Is it forbidden to resort to or act upon laws?

It is not permissible to resort to man-made laws that contradict the Sharia, nor to act upon them or implement them, as Allah states: (And judge between them by what Allah has revealed) Al-Ma'idah/49, and His saying: (But no, by your Lord, they can have no faith, until they make you [O Muhammad] judge in all disputes between them) An-Nisa/65.

However, it is permissible for the one in dire need ( اضطر ) to resort to man-made laws to repel injustice or reclaim a right, under certain conditions: that he cannot attain his right except through this means, that he dislikes and detests this recourse to judgment, and that he does not take more than his due right. The Permanent Committee has issued a fatwa permitting recourse to man-made courts out of necessity if no Sharia courts exist.

Regarding the study of man-made law and the practice of law (advocacy) within it, Sheikh Ibn Uthaymeen holds that enacting laws that contradict the Sharia is disbelief (kufr). As for learning them to repel falsehood with truth, there is no harm in it. However, if it is for the purpose of following what is in them of contradiction to the Sharia, then it is forbidden. Advocacy is permissible if its goal is to restore rights to their rightful owners, and it is forbidden if its goal is to make people prevail whether they are in the right or in the wrong.