CASA decision could narrow or reverse universal injunctions
Letter follows UPenn's agreement with White House
Supreme Court allowed the policy to be enforced with emergency stay
Lawsuit claims state policy violates federal law on school sports
27 states have passed laws limiting participation in athletics programs
Mahmoud v. Taylor ruling sets dangerous precedent
Liberal justices joined three conservatives in majority opinion
Mahmoud v. Taylor case comes from Montgomery County, Md.
Ruling leaves door open to state constitution claims
Wednesday's decision, while disappointing, leaves room for more legal challenges
