Registration was never a law in the past. It was a rule.
rule
ro͞ol/
noun
one of a set of explicit or understood regulations or principles governing conduct within a particular activity or sphere.
"the rules of the game were understood"
synonyms: regulation, ruling, directive, order, act, law, statute, edict, canon, mandate, command, dictate, decree, fiat, injunction, commandment, stipulation, requirement, guideline, direction;
formalordinance
Call is a rule, call it a law. Same thing. It was and is law.