The UK government must seek to maintain unhindered and uninterrupted data flows with the EU after Brexit otherwise its security and trade could be hindered, a cross-party group of peers warned on Tuesday 18 July.
The House of Lords' EU Home Affairs Committee, chaired by crossbencher and former diplomat Lord Jay of Ewelme, also said that Theresa May's administration had provided "little detail" on how it plans to achieve this outcome.
"The volume of data stored electronically and moving across borders has grown hugely over the last 20 years," Lord Jay said.
"Between 2005 and 2012 alone, internet traffic across borders increased 18-fold. The maintenance of unhindered data flows is therefore crucial, both for business and for effective police cooperation.
He added: "The Committee was concerned by the lack of detail on how the Government plans to maintain unhindered data flows post-Brexit. It was concerned, too, by the risk that EU and UK data protection rules could diverge over time when the UK has left the EU.
"To avoid this, the Committee urges the Government to secure a continuing role for the Information Commissioner's Office on the European Data Protection Board."
The group of peers, which looked at the General Data Protection Regulation (GDPR), the Police and Criminal Justice Directive (PCJ), the EU-US Privacy Shield and the EU-US Umbrella Agreement, found that, without a transitional arrangement, concerns would be raised about the UK's ability to maintain "deep police and security cooperation" with the bloc.
The Committee also noted that there was a consensus among its witnesses that the "most effective way" to achieve unhindered flows of data would be to secure adequacy decisions from the European Commission under Article 45 of the General Data Protection Regulation and Article 36 of the Police and Criminal Justice Directive.
Baroness Williams of Trafford, Minister of State at the Home Office, told the peers that "in a world of increasing mobile threats... data and data-sharing is one of our first lines of defence. [It is] absolutely vital that law enforcement agencies work together across borders to share information in order to protect the public".
But Matt Hancock, the digital minister, failed to tell the group how the government plans to maintain unhindered and uninterrupted data flows with the EU after Brexit. "[I do] not want to stress any particular option," he said.