Supreme Court nominee Sonia Sotomayor's thin record on the limits of presidential power suggests she will be neither reflexively hostile to broad expansion of a president's authority nor a reliable rubber stamp in support of it.

Three cases in particular offer clues:

_ As a judge on the 2nd Circuit U.S. Court of Appeals, Sotomayor dismissed complaints of commuters about random searches aimed at stopping terrorists on a ferry 300 miles north of New York City.

_ Citing an earlier ruling by the Supreme Court on the same topic, she upheld President George W. Bush's decision to prohibit U.S. aid to international family planning groups that support abortion.

_ On the other hand, Sotomayor joined colleagues in striking down parts of the anti-terror USA Patriot Act that Bush sought automatically prohibiting Internet service providers from telling customers when the government asks for private information about them.

Sotomayor has ruled in only a handful of foreign policy and national security cases that turned in part on constitutional limits to the powers enjoyed by the president, including the government's ability to respond to the threats, fears and vulnerabilities laid bare by the Sept. 11, 2001, terrorism attacks.

In those rulings, as well as a speech she gave in 2003 at the Indiana University law school, she appeared to be more willing to consider robust use of presidential authority than was Justice David Souter, the man she would replace.

Souter, who retired last week, was among the justices most skeptical of the powers asserted by the Bush administration following Sept. 11.

While Sotomayor has leaned heavily on earlier court decisions to support her rulings — as appeals court judges must — she soon could face potentially groundbreaking cases on national security if President Barack Obama asserts executive authority to continue detaining suspected terrorists.

Obama's far-reaching steps to deal with the economy also could provoke legal challenges that could make their way to the high court. The justices recently rejected a bid to stop Chrysler LLC's sale of most of its assets to Italian automaker Fiat.