A judge Friday unsealed a trove of court documents that could shed light on a secret cellphone tracking program used by police nationwide.
The judge in Charlotte, N.C., acted after a petition from the Charlotte Observer to make the documents public.
Included are 529 requests from local Charlotte-Mecklenburg police asking judges to approve the use of a technology known as StingRay, which allows cellphone surveillance.
The United States Postal Service granted almost all of the nearly 6,700 requests from law enforcement agencies last year to monitor the mail of Americans for use in criminal and national security investigations, Postal Service officials told a House panel on Wednesday.
The officials said that only 10 requests had been denied, for a rate of approval that some members of Congress sharply criticized. Cases of monitoring are called mail covers because the collected information comes from the outside of letters and parcels.
John L. Haley, who works in Baltimore City police’s phone tracking unit, denied that his unit used stingrays (devices that collect data by mimicing cellphone towers to trick cellphones into connecting to them) to surveil cellphones, but he wouldn’t elaborate further, invoking a nondisclosure agreement with the FBI.
While revelations from Edward Snowden about the National Security Agency’s massive database of phone records have sparked a national debate about its constitutionality, another secretive database has gone largely unnoticed and without scrutiny.
The database, which affects unknown numbers of people, contains phone records that at least five police agencies in southeast Virginia have been collecting since 2012 and sharing with one another with little oversight. Some of the data appears to have been obtained by police from telecoms using only a subpoena, rather than a court order or probable-cause warrant. Other information in the database comes from mobile phones seized from suspects during an arrest.