At the Investigatory Powers Tribunal, human rights groups Liberty and Privacy International alleged that MI5 was aware it was consistently breaking laws and safeguards on gathering data in bulk while illegally obtaining warrants to do maintain the practice, The Times reports.

On the first day of the landmark case against the agency, Thomas de la Mare QC said in his opening statement: “Nothing that has been done is in accordance with the law. Were it not for Liberty and Privacy International’s willingness to act, none of this would be in the public domain.”

The organisations have brought a joint case seeking to challenge the powers given to the intelligence agencies in the Investigatory Powers Act 2016, or so-called snoopers’ charter.

The issues go as far back as 2010, when an internal compliance paper recommended a retention period should be assigned to data. While the paper has been made available to the tribunal, the reason for the recommendation has been redacted.

MI5 is accused of breaching the safeguards on the period for which data could be stored as well as who could access it and on legally privileged material.

The groups also argue that successive home secretaries have overlooked and failed to investigate MI5’s breaches, despite having information that it was acting illegally.