From Minnesota Public Radio, this is Future Tense for Tuesday, July 25th. I'm Jon Gordon. Today, U.S. officials move to calm fears about an Internet surveillance system. -- Government officials say the FBI's "Carnivore" is merely a small-scale device with limited powers and insists that fears of sweeping online surveillance are overblown. Carnivore allows law enforcement agencies to find and follow the e-mails of a criminal suspect among the flood of other data passing through an Internet service provider. Privacy advocates say the program casts a net so wide that innocent people could be monitored by the FBI. The FBI's Donald Kerr told a House Judiciary subcommittee public safety depends increasingly on electronic surveillance, but said the FBI uses Carnivore sparingly. U-S Attorney General Janet Reno two weeks ago ordered a review of Carnivore to determine whether it infringes on privacy rights. Critics remain skeptical. The American Civil Liberties Union has asked for a look at the program's source code so it can evaluate the system's capabilities. The ACLU's Barry Steinhardt comments.