Is it permissible to work as a lawyer in a country that does not rule by what Allah has revealed, and is the earned money lawful or unlawful?

The lawyer who defends a false case, if he deems that permissible or does not care about violating the Shari'ah, is a disbeliever, and his earnings are unlawful (suht). However, if he believes his action is forbidden but is driven by greed, he is sinful, committing a grave sin, and his earnings are unlawful (suht). As for whoever defends his client believing him to be rightfully (muḥiqqan) in accordance with the Shari'ah and strives in that, he is rewarded and excused, and his earnings are lawful. And whoever defends a right for his brother, believing it to be a right, he is rewarded and deserves the earnings.