Chris Davis, former chair of the National Primary Headteachers' Association, said the group is not satisfied with a system that allows parents to buy their way through a legal appeals process.
He called for the implementation of a national framework of rules applying to every state school in the country, which could create a fairer system.
"That way, there would be no question about the rules. Parents would have complete clarity as to how they were going to be judged and what rules applied to them," Mr Davis added.
His comments follow the release of a BBC report, which found parents around the country are spending as much as £2,000 on legal advice to help their child get into the state school of their choice.