Answer:
It was located inside a county building.
Step-by-step explanation:
According to Blackmun’s decision, the crèche display violated the establishment clause because it was located inside a county building.
According to the passage, it is clear that the crèche violated the establishment clause because the crèche in the main staircase was the one sending the message that the county is promoting the Christian praise to God not the Hanukkah menorah outside the county building.