The Intercept reported that nine human rights and civil liberties bodies had written to the US Justice Department, objecting to the agreement that is sought to be struck under the CLOUD Act that was signed into law by US President Donald Trump in March.
The Act was primarily meant to make it possible for American law enforcement organisations to gain access to data held by American tech firms in foreign countries; the need for it was accelerated by a case in which Microsoft was refusing to hand over data on its mail servers in Ireland to the FBI. This data was claimed to be needed in a drug trafficking case.
But the CLOUD — Clarifying Lawful Overseas Use of Data — Act also allows for deals between the US president and other countries to give foreign law enforcement agencies the authority to obtain data from US tech companies without a warrant. The only condition is that the target is not someone who is either a citizen of, or resident in, the US.
Australia has also expressed interest in such a deal. During parliamentary committee hearings on the Australian Government's encryption bill, Labor Shadow Attorney-General Mark Dreyfus raised the issue of the CLOUD Act, asking a number of Americans who appeared before the committee as to whether the Australian bill would allow a deal with the US under the CLOUD Act.
The Intercept cited a possible scenario for the type of co-operation the UK is seeking, as outlined by the Electronic Frontier Foundation in September.
To quote the EFF: "London investigators want the private Slack messages of a Londoner they suspect of bank fraud. The London police could go directly to Slack, a US company, to request and collect those messages. The London police would receive no prior judicial review for this request. The London police could avoid notifying US law enforcement about this request. The London police would not need a probable cause warrant for this collection."
This could, however, put the privacy of Americans at risk and expose them to abuses of the Fourth Amendment that prohibits unreasonable searches and seizures.
While the CLOUD Act prohibits foreign law enforcement agencies from "intentionally targeting" an American resident or citizen, it does not prevent the foreign agency from seizing communications from Americans. If a British person under suspicion had been communicating with Americans, then the British law enforcement agency could also seize those communications.
And then such communications could be shared with American agencies. The means of collection would make the data unusable in an American court, but American agencies could re-acquire the communications after getting a warrant, a practice known as "parallel construction".
US agencies like the FBI and the Drug Enforcement Agency, already use information from the NSA's warrantless wiretapping programs in this manner.
Apart from the EFF, the other eight organisations to sign the letter to the Justice Department are Human Rights Watch, Access Now, Demand Progress, Fight for the Future, Freedom of the Press Foundation, Government Accountability project, Restore the Fourth and World Privacy Forum.