OTTAWA – The Canadian whistleblower at the centre of the Cambridge Analytica data scandal is offering extended testimony at the House ethics committee today.

Chris Wylie—the former Cambridge Analytica employee who spoke out alleging the improper harvesting of information from millions of Facebook users for political purposes—is appearing before the Access to Information, Privacy and Ethics Committee for three hours Tuesday.

Between 8:45 and 11:45 a.m. Wylie is appearing via video, from London, U.K.. The meeting is televised, and it’s expected he will receive a grilling from all sides as the committee has been digging into the breach of personal information involving Cambridge Analytica and Facebook.

As The Canadian Press first reported, Wylie was also contracted by the federal Liberal Party’s research bureau in early 2016 for $100,000 to help set up social media monitoring tools among other information gathering tasks.

Facebook estimates that of the 87 million users worldwide that were affected, more than 600,000 users in Canada had their data improperly shared with Cambridge Analytica.

Since mid-April the committee has heard from over a dozen witnesses, including Privacy Commissioner of Canada Daniel Therrien, who is probing the impact on Canadians’ data, and Facebook’s compliance with federal privacy laws.

With files from the Associated Press