According to CNN:
Sending dual signals in ruling on this issue for the first time in a quarter-century, the high court said that displays of the Ten Commandments -- like in their own courtroom frieze -- are not inherently unconstitutional. But each exhibit demands scrutiny to determine whether it goes too far in amounting to a governmental promotion of religion, the court said in a case involving Kentucky courthouse exhibits.
In effect, the court said it was taking the position that issues of Ten Commandments displays in courthouses should be resolved on a case-by-case basis.
In that 5-4 ruling and another decision involving the positioning of a 6-foot granite monument of the Ten Commandments on the grounds of the Texas Capitol, Justice Sandra Day O'Connor was the swing vote. The second ruling, likewise, was by a 5-4 margin.
The Kentucky Opinion can be found here. (Display Unconstitutional)
The Texas Opinion can be found here. (Display Constitutional)