In ancient times, when the Mass of the Catechumens ended, and before the Offertory began, the deacon directed the Catechumens and all non-Catholics to leave.
When did this change? Were there any decrees ending this law or practice, or was it just a custom that ceased over time?
How would you respond to a Catholic today who says that it's sacrilegious for an unbeliever to attend Mass after the Mass of the Catechumens has ended?