It is not possible to make a public law to convey natural born citiazenship. A person is either born a natural born citizen without the act of a public law, or a person who is not a natural born citizen is made to have some or all of the rights of a natural born citizen at birth or after the birth. The legal principle of ius soli or jus soli is the use of a public law to make a person naturalized at birth like an actual natural born citizen, just as a person may be naturalized by public law at some dte after the birth of the person.
There was no need to legislate a public law to define a natural born citizen, because doing so would perforce result in every person being naturalized at birth or after birth, because no one would qualify any longer as a natural born citizen. A person cannot be a natural born citizen if and when a public law is required to make them a natural born citizen.
Exactly!