There are friends of mine who say that as long as the rulers govern by what opposes Allah’s legislation, and it is mentioned in the Qur’an that whoever does that is a disbeliever, therefore we can make takfir of the rulers. I can’t find anything to reply to them with and do not know how to convince myself that this is wrong. تكفير الحكام.

Praise be to Allah, and may Allah’s peace and blessings be upon the Messenger of Allah, his family and his companions.

As to what follows:

In response to your question, we say, and with Allah Almighty lies all success:

Unrestricted takfir of rulers and others is from the methodologies of the deviants and Khawarij. So it is obligatory to take one’s time and not hasten concerning the issue of takfir, as it requires two things:

Firstly: verification that the act carried out by the individual is a cause for kufr (disbelief).

Secondly: fulfillment of conditions [of takfir] and absence of preventive measures [against takfir] to pass judgment on the individual.