See the numerous cases and citations I posted previously.
"When my father said “shall,” we all knew what he meant. When my teachers said “shall,” we all knew what they meant. And when the Lord said “shall” in the Ten Commandments, we all knew what that meant. In the old days, “shall” meant “shall.”
“Not so,” says Justice Antonin Scalia.
In Castle Rock vs. Gonzales, the Supreme Court took the meaning of the word “shall” and redefined it to mean “maybe or maybe not.” Such a distortion is perplexing at best.
https://www.denverpost.com/2005/07/14/what-does-shall-mean/