Chief Judge Beryl A. Howell of the U.S. District Court for the District of Columbia released the information following a petition by investigative journalist Jason Leopold, now with BuzzFeed, that was joined by the Reporters Committee for the Freedom of the Press. (Katherine Frey/The Washington Post)

Sealed law enforcement requests to track Americans without a warrant through cellphone location records or Internet activity grew sevenfold in the past three years in the District, new information released by a federal judge shows.

Details about the growth come as the U.S. Supreme Court weighs whether to rein in such rapidly expanding demands.

Legal experts said the disclosure Monday appears to mark a first, and that neither the Justice Department nor private companies have previously made public such specific data about how often law enforcement agencies seek those court orders.

The summary data gave counts of requests by year from 2008 through 2016 made in criminal cases handled by the Justice Department or U.S. attorney’s office for the District. Details about each individual case, such as the name of a suspect or what records were sought, were not disclosed.

The requests were made under a 1986 statute that enables law enforcement agencies to obtain court orders requiring ­communication service providers to turn over records about individual customers. The orders do not apply to information about telephone calls, such as the time, date, duration and numbers dialed, which can be obtained in other ways.

Instead, the requests seek individuals’ Internet connection records or cellphone tower records. Those records exclude the content of communications but can be highly valuable to investigators seeking to establish a history or pattern of movement, conduct or relationships.

The information requests can include Internet browsing logs and activity; the time, date, size, sender and recipient of email, instant or social media messages, or other transaction records; as well as computer identification numbers and information about websites that a user accessed.

The tallies were released as part of an open-records lawsuit brought by journalists to unseal a much larger collection of information about court-ordered electronic surveillance in closed criminal investigations in the nation’s capital.

James X. Dempsey, executive director of the Berkeley Center for Law & Technology, said that the data confirms the common-sense conclusion that secret law enforcement requests for phone and Internet records have surged as they have become routine in criminal cases. He said that the data probably will be noted in a pending Supreme Court debate over the extent of privacy protections and surveillance technology.

The Supreme Court in 2014 ruled unanimously that police generally must obtain a warrant to search the contents of cellphones. Last month, it announced that it will decide next term whether law enforcement agencies need a warrant to track suspects’ locations through cell site location records, in a challenge brought by a criminal defendant convicted after police obtained five months’ worth of his location data from his phone company.

Lower courts have said that ­decades-old privacy rulings may need to be updated to account for society’s reliance on rapidly changing technology.

For example, appellate courts are also weighing whether a warrant is required by law enforcement agencies to covertly collect cellphone information using new devices that mimic cell towers to elicit data from targeted numbers.

Separately, major technology companies including Facebook and Google also have objected to court orders that prohibit them from letting users know when law enforcement investigators ask to search their political communications.

The information release for the District shows that as of 2014, requests for Internet activity and phone-location records began to exceed and now far outnumber requests for telephone metadata, such as the timing and duration of calls to or from specific phone numbers.

Requests for records of Internet activity and phone location hovered between 55 and 160 from 2008 to 2013 before jumping to 334 in 2014, 581 in 2015 and 1,136 in 2016, according to this week’s release. By comparison, the D.C. federal court previously reported that metadata requests have ranged from 329 in 2006 to a low of 189 in 2016.

Chief Judge Beryl A. Howell of the U.S. District Court for the District of Columbia released the information following a petition by investigative journalist Jason Leopold, now with BuzzFeed, that was joined by the Reporters Committee for the Freedom of the Press.

They seek all government electronic surveillance applications and orders in closed investigations that directed private service providers to turn over users’ call information as well as information related to tracked devices, stored emails or customer records.

The latest count may have missed some requests because the court clerk’s office relied on a search of header information in its electronic case-filing system and overcounted others if a particular request was renewed for more than one year, Howell wrote in a court notice.

But neither potential error would necessarily account for the three-year surge in the Internet search requests.

Jeffrey Louis Light, Leopold’s lawyer, said he had “no idea” why the volume of requests has surged, “but I now know this is the next question to ask.”

“We’re starting to put together the framework of how the government has been using these various tools at its disposal, and how it has changed over time,” Light said. “I certainly hope that other district courts would eventually make these kinds of numbers available as well.”

Under current law, prosecutors seeking Internet connection and cell-tower records are not required to obtain a search warrant, which requires showing a judge probable cause that a crime has been committed. Instead, they need to meet a lower legal threshold, offering reasonable grounds to believe the records they are after are “relevant” to an ongoing criminal investigation.

Dempsey said the spike and volume of such requests in the District will factor into the Supreme Court deliberations.

“The government, in arguing against warrants, will say this has become a standard technique and often one of the first steps we take in an investigation before we’ve even established probable cause, and requiring us to obtain a warrant will cut off an important building block of many investigations,” Dempsey said.

He added that those seeking a warrant requirement “will say, look, this has gotten out of control. . . . It’s time for the court to make it clear this information is highly sensitive and revealing and therefore should only be obtained in the later stages of an investigation.”

Katie Townsend, litigation director for the Reporters Committee for the Freedom of the Press, said that the government’s use of such orders “is shrouded in secrecy.”

“Not only do individuals not know that their communications records are being sought from third parties,” she said, “but applications are filed on dockets that are not public, and they are generally kept under seal, often permanently.”

She added, “We think it is critically important that there be more transparency when it comes to these kinds of legal demands.”

A spokesman for the Justice Department did not immediately respond to a request for comment. The office of U.S. Attorney Channing D. Phillips of the District has said in court filings that it agreed in principle that surveillance cases did not necessarily need to be permanently sealed, and has agreed to some earlier disclosures.