The fact-checking website PolitiFact chooses one lie each year to elevate to its LIE OF THE YEAR.
You'll probably not be shocked to hear this, but the 2019 winner is Donald Trump. I admire the diligence of the PolitiFact staff. I would hate to have to wade through the thousands of lies Trump tells in a year, and try to decide which is the biggest lie.
Here is a small part of what they had to say this year:
Every year, PolitiFact editors review the year’s most flagrant inaccuracies in search of a significant false claim that can be elevated to Lie of the Year.
The distinction is awarded to a statement that is more than ridiculous and wrong. The Lie of the Year — the only time PolitiFact uses the word "lie" — speaks to a falsehood that proves to be of real consequence and gets repeated in a virtual campaign to undermine an accurate narrative.
The whistleblower, who to Trump’s consternation remains unidentified, raised the concern that the president’s actions leading up to and on that phone call amount to interference in the coming presidential election. Agree or disagree with the conclusion, or whether the president’s conduct warrants impeachment, the actions described in the complaint stand up to factual scrutiny.
The claim that the whistleblower got his phone call "almost completely wrong" is PolitiFact’s 2019 Lie of the Year.