Consumers accused Apple of illegal conduct in a class action lawsuit filed against the company over allegations Siri quality control contractors eavesdropped on personal conversations without users’ consent.

The lawsuit was filed yesterday (7 August) in California, Apple’s domestic US state, led by two plaintiffs, one of which is a child acting through a guardian. They allege the voice assistant regularly recorded conversations without being initiated either through a spoken wake phrase or the press of a button on compatible devices, arguing this constituted a lack of permission.

Further, the plaintiffs claim Apple “knows that unauthorised recordings are common” because the company “tasks its human reviewers with, among other things, identifying whether Siri was deliberately activated or not”. They state the vendor had failed to notify customers “they are regularly being recorded without consent”.

They argued the lack of authorisation breaches Californian law, while adding children which may have been given or have access to an Apple device “never consented to being recorded” either directly or through a parent.

The lawsuit referred to a recent report by The Guardian, which stated the recording of non-consensual conversations by Siri was commonplace and had revealed deeply personal details including medical information.

Apple swiftly suspended the so-called Grading system operation while it assesses the privacy implications, and pledged to offer a clear opt-out to consumers when the service resumed.

The set-up was designed to weigh the quality of responses Siri delivered to improve its performance.

Plaintiffs in the lawsuit are seeking to expand its scope to consumers from other US states and called for damages of $5,000 per violation.