By Theodoric Meyer and Peter Maass

Update June 6, 2013: This post has been revised to reflect reports of regular FBI and National Security Agency surveillance of domestic phone records under a provision of the Patriot Act. It was originally published Dec. 4, 2012.

The U.S. government isn’t allowed to wiretap American citizens without a warrant from a judge. But there are plenty of legal ways for law enforcement, from the local sheriff to the FBI to the Internal Revenue Service, to snoop on the digital trails you create every day. Authorities can often obtain your emails and texts by going to Google or AT&T with a simple subpoena. Usually you won’t even be notified.

The latest twist: A secret court order made public by the Guardian newspaper on Wednesday shows that the FBI has successfully requested call “metadata” — including the time, duration and location of phone calls, though not what was said on the calls — under provisions of the Patriot Act. Signed by senior federal Judge Roger Vinson on April 25, the order directs Verizon Business Network Services to provide all call information to the National Security Agency each day for a three-month period.

Whether such sweeping surveillance requests should be allowed under the Patriot Act is a matter of heated debate in Congress. Sen. Dianne Feinstein, D-Calif., who chairs the Senate Select Committee on Intelligence, suggested on Thursday that Vinson’s order was just a regular renewal of surveillance that’s taken place for years. But disclosure of the order also prompted calls to rein in the practice, including from Sen. Richard J. Durbin, D-Ill., the No. 2 Democrat in the Senate. On another front, two senators introduced legislation in March to bolster privacy protection for emails; action is pending.

Against that backdrop, here’s a look at how law enforcement can track you without a warrant:

Read More No Warrant, No Problem: How the Government Can Get Your Digital Data – ProPublica.