By some accounts, having Judge Sonia Sotomayor replace retiring Justice David Souter wouldn't shift the Supreme Court appreciably in the closest cases that divide the justices philosophically.
But the final days of the term that wraps up this week show that predicting the behavior of nine independent jurists is imprecise business, no matter how well you think you know their tendencies.
This will get lost in the ferocious political theater that consumes Sotomayor's confirmation hearing in mid-July. Supporters and detractors will look for guarantees or pronounce their own definitive conclusions regardless of how flimsy the evidence.
But remember that whatever their views, the justices must decide the cases that come to them. And sometimes they surprise.
On Thursday, eight of them concluded that middle school officials in Arizona violated the Fourth Amendment by strip-searching a 13-year-old girl for prescription-strength Ibuprofen. That was just two months after arguments during which only Justice Ruth Bader Ginsburg seemed to appreciate the mortification of a strip search. Souter questioned why it wasn't reasonable for a school official to embarrass a student rather than have others overdose on illicit drugs at lunchtime.
But, in perhaps his last majority opinion, he called the search unreasonable because "the content of the suspicion failed to match the degree of intrusion."
Justice Clarence Thomas, on the other hand, would have given school officials broader authority and said they had no obligation to call the girl's parents before searching her.
To read the complete editorial, visit The Fort Worth Star-Telegram.