There most certainly was...
Neh 8:4 And Ezra the scribe stood upon a pulpit of wood, which they had made for the purpose; and beside him stood Mattithiah, and Shema, and Anaiah, and Urijah, and Hilkiah, and Maaseiah, on his right hand; and on his left hand, Pedaiah, and Mishael, and Malchiah, and Hashum, and Hashbadana, Zechariah, and Meshullam.
Neh 8:5 And Ezra opened the book in the sight of all the people; (for he was above all the people;) and when he opened it, all the people stood up:
Neh 8:6 And Ezra blessed the LORD, the great God. And all the people answered, Amen, Amen, with lifting up their hands: and they bowed their heads, and worshipped the LORD with their faces to the ground.
Neh 8:7 Also Jeshua, and Bani, and Sherebiah, Jamin, Akkub, Shabbethai, Hodijah, Maaseiah, Kelita, Azariah, Jozabad, Hanan, Pelaiah, and the Levites, caused the people to understand the law: and the people stood in their place.
Neh 8:8 So they read in the book in the law of God distinctly, and gave the sense, and caused them to understand the reading.
Ezra was speaking from the 'seat of Moses'...
That is an interesting theory, but I'm going with a more traditional understanding; The seat of Moses referred to the chair, a literal chair, of the chief Justice that differed from the seats of the other judges in the court. It was the symbol of Jewish legal authority conferred upon judges (שופטים) akin to a king’s throne. The office was established by Moses.
It is good to know that Protestants acknowledge a precedent for a Magisterium, though.
Peace be with you.