The New York Times and the National Football League have been going at it since the Times report documenting ways the league relied on faulty concussion research.
Earlier this week, attorney Brad Karp wrote a letter to the Times on behalf of the NFL demanding a retraction, claiming "the story did not show any meaningful 'ties to the tobacco industry.' Nor did it present a shred of evidence to support its thesis that the NFL intentionally concealed concussion research data."
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The Times was obviously going to respond, and instead of cowering, it decided to take an aggressive approach with a strongly worded letter.