The intelligence community inspector general issued a statement Monday refuting false claims by President Trump and his allies about the whistleblower whose complaint on Trump's interactions with Ukraine triggered a formal impeachment inquiry.

Why it matters: It's rare for the Office of the Inspector General of the Intelligence Community to issue such a statement. But it did so after the president and loyalist lawmakers made false claims while attacking the whistleblower's credibility over the complaint concerning Trump urging Ukraine to investigate his political rival Joe Biden and his family.

Context: Trump incorrectly stated that rules for whistleblowers had recently changed to not require firsthand information.

The claims seem to have been based on a since debunked report by the conservative site The Federalist about the whistleblower complaint form being revised.

The president and his loyal defenders on Capitol Hill also claimed incorrectly that the whistleblower lacked firsthand knowledge of the information in the report. Sen. Lindsey Graham (R-S.C.) accused the whistleblower of using "hearsay."

Key takeaways: The inspector general makes clear that these claims are inaccurate and that by law the complainant "need not possess first-hand information in order to file a complaint or information with respect to an urgent concern."

The inspector general also notes that the whistleblower "stated on the form that he or she possessed both first-hand and other information" and that they had "direct knowledge of certain alleged conduct."

What they're saying: The whistleblower's lawyer Mark Zaid issued a statement welcoming the inspector general's statement.

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