D adopted an ordinance restricting admission to certain dance halls to persons between the ages of 14 and 18. D authorized the licensing of 'Class E' dance halls. They provided a place where teenagers could socialize with each other, but not be subject to the potentially detrimental influences of older teenagers and young adults. Stanglin (P) operates the Twilight Skating Rink. P obtained a license for a Class E dance hall. He divided the floor of his roller-skating rink into two sections with moveable plastic cones or pylons. On one side of the pylons, persons between the ages of 14 and 18 dance, while on the other side, persons of all ages skate to the same music -- usually soul and 'funk' music played by a disc jockey. No age or hour restrictions are applicable to the skating rink. Most of the patrons are strangers to each other, and the establishment serves as many as 1,000 customers per night. P sued D to enjoin enforcement of the age and hour restrictions of the ordinance. P claimed it violated substantive due process and equal protection and infringed on the rights of those 14 and 18 to associate with persons outside that age bracket. The trial court upheld the ordinance; it was rationally related to P's legitimate interest in ensuring the safety and welfare of children. The Texas Court of Appeals upheld the time restriction, but it struck down the age restriction. The age restriction violated the First Amendment associational rights of minors. It held that D's stated purposes may be achieved in ways that are less intrusive on minors' freedom to associate. D appealed. '