What the Oral Torah Says About This
Deuteronomy 4:2 and 13:1
The Pharisees discussed the prohibitions against adding to or taking away from the laws of the Torah (Deuteronomy 4:2 and Deuteronomy 13:1). They called these prohibitions 'Bal Tosif' and 'Bal Tigra'.
Maimonades Law of Rebellion 2:9
Ecclesiastes Rabba 3:1
B. Megillah 14a
These are pronouncements on the substantive law of Torah that have not followed the procedural laws of Torah. Torah procedural laws tell us that substantive laws can only be made by Priests, Levites and Judges.
The quicker we recognise and accept that the replacement of Priests, Levites and Judges by the Pharisee Scholars was an accident of political history that needs to be put right, the better.