During the trial, it emerged that Facebook was violating Illinois law by storing biometric data – digital scans of people's faces, in support of its face-tagging feature – without users' consent.

The new law paves the way for Google and Facebook to invest tens of millions of dollars in local content deals, and could prove a model for resolving the firms' tussles with regulators worldwide.

The move responds to concerns about violence and other inappropriate content which may be viewed by minors on the massive video-sharing platform.