The investigation into a Maryland prosecutor's death is raising questions about the confidentiality of electronic toll records.

Jonathan Luna, an assistant U.S. attorney, was murdered in Pennsylvania, and investigators are still trying to figure out why he wasn't home asleep in Maryland. Police used E-ZPass records from the Pennsylvania Turnpike to try to piece together his last night's travels. The E-ZPass system is used to prepay toll charges, which are recorded each time the vehicle passes through the tollbooth. An E-ZPass subscriber's vehicle is equipped with a radio frequency identification (RFID) tag, a microchip that responds to a radio query at the tollbooth with a unique ID code.

The Luna case is not the first time E-ZPass toll records have been sought in a criminal investigation, but the high-profile case has focused attention on what some consider another breach of public trust by the government. At issue is how long the data is retained and who has access to it.

A Pennsylvania Turnpike spokeswoman wouldn't comment on the Luna case specifically, but said she remembers just a few cases where law enforcement requested information via a subpoena, adding that those also were high-profile matters and there could have been more. She said the information is released only in response to a subpoena.

Robert Bulmash, founder of Private Citizen, a Chicago-based organization aimed at fighting privacy abuse, said E-ZPass and other similar collection systems leave a trail of confidential information on their customers -- a trail that should not exist.

"I talked to my own toll way system [in Illinois] some time ago when they first installed it," Bulmash said. "I said, 'You don't need the billing information after three months. Why don't you dump it after three months?' They said, 'That's not going to be our policy.'"

Doug Hanchett, director of media relations for the Massachusetts Turnpike Authority said records there are kept on hand for six months, archived for another two years, then destroyed.

Privacy advocates question why the records are kept for so long. "I'm going through Plaza 51 headed west at 3:45. Why is it their business to keep a record of it? All they need is my 40 cents," Bulmash said. "That they keep a record of it is an absurdity. It's not their business."

Lee Tien, an attorney at the Electronic Frontier Foundation, a San Francisco-based nonprofit group formed to protect the digital rights of individuals, said personal data should never be kept longer than needed for its original purpose. Tien said electronic toll technology presents a big privacy issue. "There are several concerns, depending on the system architecture," he said, adding that toll data can be mined to reconstruct a person's driving history, which can be shared or even sold. Some technologies make it possible to track drivers in real time, Tien said.

Bulmash doesn't blame investigators for using toll information. "There's nothing wrong with taking advantage of it if it's there, and if it's for a criminal investigation."

But Bulmash fears it's a slippery slope leading to use of that information for other purposes. "Say Sam Jervanovic is dating Jane Doe, and Sam's wife finds out and requests [through subpoena] the toll way records to find out where Sam was going at 3:45 on Tuesday? What's the level of privacy? If the information is there, it's obtainable."

The technology, though useful, gives the government too much access to citizens' private lives, and government record keeping can get out of hand, Bulmash said. "The Germans in the 1930s liked to keep records. They kept volumes of records that came in handy. Our census bureau kept records on the Japanese, swearing they would never use these for any manner other than to numerate, and boom, it was used for a different purpose after World

Jim McKay, Justice and Public Safety Editor  |  Justice and Public Safety Editor