From whom is the stronger opinion taken in matters of scholarly disagreement?

The questioner : Shaykh, regarding the issue of determining the stronger opinion, from which person is it accepted, and does he need to have a specific quality, such as knowledge of hadith?

The Shaykh : The answer to this has already been given, may Allah reward you. Did we not divide people into a scholar qualified to derive rulings and a scholar who follows a scholar without knowing his evidence?

The questioner: Yes.

The Shaykh : Okay, the one who wants to determine the stronger opinion must be knowledgeable of the Book and the Sunnah.

The questioner : Yes, may Allah reward you with good.