The case the court was hearing Tuesday is in many ways the flip side of the emotional argument over school vouchers. The high court cleared the way for government-funded vouchers programs in 2002.
The latest case asks not whether governments can use tax money to underwrite religious education, as the voucher question did, but whether when money is available, it must be available equally.
The case concerns a former college student who won and then lost a merit scholarship offered by the state of Washington. Joshua Davey lost the money when he declared theology as his major.
Like 36 other states, Washington prohibits spending public funds at schools that are religiously affiliated. The bans, known as Blaine amendments, date to the 19th century when anti-Catholic sentiment ran high.
Davey and his backers say the state law is discriminatory and violates the Constitution's guarantee of freedom of religion. The state argues the policy did Davey no harm.
A ruling in Davey's favor could overturn Blaine amendments everywhere.
Davey's opponents at the Supreme Court have argued that the matter boils down to the states' rights to spend their money as they see fit.
The Davey case is one of two major church-state debates at the high court this year. The other concerns a California atheist who wants to strip the phrase "under God" from the Pledge of Allegiance.
Davey has since abandoned his ambition for the ministry in favor of Harvard Law School, but said he is still bothered that the state seemed to slight his first choice.
"From my perspective it was very unfair and kind of arbitrary," said Davey, a devout Christian.
"I was being told that that value wasn't important and wasn't worth the state's money."
The case began in 1999, when Davey qualified for a Promise Scholarship, a state-funded program for high-achieving students of modest means. The scholarship of about $3,000 never came through, because Davey decided to study for the ministry at Northwest College in Kirkland, Wash.
Davey sued in federal court three years ago. The San Francisco-based 9th U.S. Circuit Court of Appeals sided with Davey last year, finding that the state had no compelling interest in limiting what he could study.
A ruling from the Supreme Court is expected by summer.
The case is Locke v. Davey, 02-1315.
In related news:
The case will be closely watched by businesses, which fear the court will open them up to more lawsuits.
The case is Pennsylvania State Police v. Nancy Drew Suders, 03-95.
LaShawn Banks was taking a shower when masked and heavily armed officers broke into his Las Vegas apartment in 1998 looking for drugs.
The Supreme Court used his case to clarify how long police must wait before breaking into a home to serve a warrant. The court ruled 9-0 that if police had waited any longer than 20 seconds, a drug suspect could be flushing evidence down the toilet.