What is changing? The expiry of the Patriot Act brings to an end bulk collection of Americans’ phone metadata – who called who, when and for how long, but not the content of calls – by the US. Under the USA Freedom Act, records must be held by telecommunications companies and investigators need a court order to access specific information. Technology companies will be given greater leeway to reveal data requests. The measures are intended to balance concerns on privacy with providing the authorities the tools they need to prevent attacks.

What stays the same? Key parts of the Patriot Act are retained in the Freedom Act. They include the provision allowing the monitoring of “lone wolf” suspects – potential attackers not linked to foreign terror groups, despite the US authorities admitting the powers have never been used. The Freedom Act also maintains a provision allowing investigators to monitor travel and business records of individuals, something law officers says is more effective than bulk collection.