The FBI wants greater authority to hack overseas computers, according to a law professor.

A Department of Justice proposal to amend Rule 41 of the Federal Rules of Criminal Procedure would make it easier for domestic law enforcement to hack into the computers of people attempting to protect their anonymity on the internet.

The change in search and seizure rules would mean the FBI could seize targets whose location is "concealed through technological means", as per the draft rule (key extract below). Concealed through technological means is legal speak for hosted somewhere on the darknet, using Tor or proxies or making use of VPN technology.

Authority to Issue a Warrant. At the request of a federal law enforcement officer or an attorney for the government: (6) a magistrate judge with authority in any district where activities related to a crime may have occurred has authority to issue a warrant to use remote access to search electronic storage media and to seize or copy electronically stored information located within or outside that district if: (A) the district where the media or information is located has been concealed through technological means; or (B) in an investigation of a violation of 18 U.S.C. § 1030(a)(5), the media are protected computers that have been damaged without authorization and are located in five or more districts.

The DoJ has said that the amendment is not meant to give courts the power to issue warrants that authorise searches in foreign countries.

However the "practical reality of the underlying technology means doing so is almost unavoidable", according to Ahmed Ghappour, a visiting professor at UC Hastings College of the Law.

Ghappour argues that the proposals would result in "broadest expansion of extraterritorial surveillance power since the FBI’s inception".

Asked whether the FBI enhanced extraterritorial power might encroach on the NSA's turf, Ghappour told El Reg that the issue goes further than that and might also affect the US State Department and CIA. "Uncoordinated unilateral 'cyber' ops by FBI may interfere with US foreign affairs (or covert ops)," he said. Security experts think Ghappour may well be onto something on this point.

"Malware from the FBI to, say, Syria could very well trigger congressional investigations," noted Matthew Green, an assistant research professor who lectures in computer science and cryptography at Johns Hopkins University, in an update to his Twitter account.

The FBI reportedly used malware to identify users sharing child abuse images on the dark net as part of its bust of Freedom Hosting last year. In addition, LulzSec kingpin-turned-FBI snitch Hector Xavier “Sabu” Monsegur reportedly led cyber-attacks against foreign governments while under FBI control, so there's evidence that the FBI is already involved in overseas cyber-ops of one form or another. Viewed from this perspective, the proposed DoJ changes would involve regulating actions and operations that are already taking place.

Professor Ghappour - who also serves as director of the Liberty, Security and Technology Clinic – has put together a detailed blog post at ‪justsecurity.org‬ breaking down the DoJ's proposal here. ®