A criminal case on its way to the Delaware Supreme Court could help define personal privacy and how far police can go when using electronic surveillance in Delaware. The American Civil Liberties Union filed a brief urging the state justices to uphold a lower court ruling barring police from using GPS without a court-approved warrant.

"This case is especially important because of its impact on the privacy rights of all Delawareans, including the vast majority who will never be charged with a crime," write ACLU attorney Richard Morse and Ballard Spahr partner Beth Moskow-Schnoll in their brief.