ash-Shawkānī:

If you have nominated yourself for giving legal rulings to questioners and judging between two disputants, know that you are being tested and afflicted and others are being tested and afflicted through you; because blood is being spilled by your verdicts, wealth and rights are being removed from their rightful owners, what is unlawful is legalised and what is unlawful is prohibited. You are saying things which Allah ﷻ never said, with no legal evidence from the book of Allah or the Sunnah of His Messenger. Rather, you are saying things that, through your own admission, you do not know whether they are true or false.

So, what will be your answer when you stand in front of Allah ﷻ? Indeed, Allah has ordered the rulers of the worshippers of Allah ﷻ to rule between them by what Allah ﷻ has revealed, and you do not know what Allah  has revealed because you do not know the way He revealed it. Allah ﷻ ordered the Muslim rulers to rule by the truth and you do not know what the truth is. You just heard some people saying something so you said it too. Allah ﷻ ordered the Muslim rulers to rule between the people with justice, and you do not know justice from oppression, because justice is what agrees with what Allah ﷻ has prescribed, and oppression is what goes against that.

These orders do not include you, in fact the ones who are ordered to carry them out are others, namely scholars, so how have you performed a task which you were not ordered to do, nor designated as a substitute to carry out in the absence of someone else. How did you proceed to give a legal ruling based on principles other than what Allah ﷻ has revealed? You became from amongst those about whom it was said: and whosoever does not rule by what Allah ﷻ has revealed, then they are the oppressors, and whosoever does not rule by what Allah ﷻ has revealed are evildoers, and whosoever does not rule by what Allah ﷻ has revealed are disbelievers’.”