Google is investigating recent actions by Margaret Mitchell, who helps lead the company's ethical AI team, Axios has confirmed.

Why it matters: The probe follows the forced exit of Timnit Gebru, a prominent researcher also on the AI ethics team at Google whose ouster ignited a firestorm among Google employees.

What's happening: According to a source, Mitchell had been using automated scripts to look through her messages to find examples showing discriminatory treatment of Gebru before her account was locked.

• The AI ethics team has been under great stress since Gebru's exit, while thousands of people both within and outside of Google have criticized the company's actions.
• Google CEO Sundar Pichai said in a December memo that the company was looking further into its treatment of Gebru. Google has yet to detail any findings from that inquiry.
• Workers cited that treatment as among the reasons for forming a minority union for employees at Google parent firm Alphabet.

What they're saying: In a statement, Google confirmed that Mitchell's email account has been locked and that the company is investigating why Mitchell downloaded a large number of files and shared them with people outside the company.

• Mitchell did not immediately respond to an e-mail seeking comment.

Between the lines: Earlier Tuesday, Mitchell had posted a tweet critical of Google CEO Sundar Pichai's planned meeting with historically Black college and university leaders, writing:

• Gebru tweeted earlier Tuesday that Mitchell's corporate e-mail appeared not to be working.

What's next: "We are actively investigating this matter as part of standard procedures to gather additional details," a Google representative said.

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