The chief priests, scribes, and elders = a delegation from the Sanhedrin (Jewish supreme court, ~70 members). This is a significant escalation — Jesus is now on their turf in Jerusalem, confronting the highest authority in Israel.

The three groups named together signal a Sanhedrin delegation — the highest court of the land based in Jerusalem. They had power to execute (lost ~30 AD per the Talmud, which is why they needed Pilate to kill Jesus in John 18:31). They also had power to rule on biblical interpretation — they were effectively "God's living interpretation body." This confrontation is new: Jesus had conflicts with local Pharisees before, but now he's in Jerusalem where the Sanhedrin has direct authority. They're asking about the temple cleansing specifically, not his teaching or miracles.