The explosive whistleblower complaint became a talking point for Musk’s attorneys throughout the testy hour-and-a-half hearing, which was scheduled for the attorneys to request more information on Twitter’s data on spam and bots — the key point in Musk’s claim that he was misled and can therefore back out of the deal. The complaint, which was obtained by The Washington Post and cited by Musk’s attorneys, alleges egregious security deficiencies and ineffective methods for counting bots at the social media giant.

For Musk’s lawyers, it was the opening salvo in a strategy that is expected to lean more heavily on the claims of whistleblower Peiter Zatko, Twitter’s former head of security.

“Mr. Zatko, who was responsible for much of this — including processing and removing various spam bots — he was not some low-level employee,” said Musk’s attorney Alex Spiro. “He was one of the top handful of officers in the company.”