On Tuesday, MSNBC’s Lawrence O’Donnell told viewers that Russian oligarchs had co-signed on Trump’s Deutsche bank loans.

“I may have some information, in this next hour, which would add a great deal to their understanding of that, if true, and I’ll be discussing it here,” O’Donnell told Rachel Maddow.

Even though he wasn’t certain about the truthfulness of the story, O’Donnell still reported it.

“I stress ‘if true,’ because this is a single source who has told me that Deutsche Bank obtained tax returns… this single source close to Deutsche Bank has told me that Donald Trump’s loan documents there show that he has co-signers. That’s how he was able to obtain those loans and that the co-signers are Russian oligarchs.”

“If true that would be a significant factor in Vladimir Putin’s publicly stated preference for presidential candidate Donald Trump over presidential candidate Hillary Clinton,” he added.

NBC News has not mentioned whether O’Donnell will be faced with any disciplinary action for reporting the false story.

Watch:

On Wednesday, O’Donnell retracted his false story by tweeting, “Last night I made an error in judgment by reporting an item about the president’s finances that didn’t go through our rigorous verification and standards process. I shouldn’t have reported it and I was wrong to discuss it on the air. I will address the issue on my show tonight.”

Error in judgment?! O’Donnell knew exactly what he was doing!

Trump’s legal team sent a letter to NBC Universal executives about O’Donnell’s false claim.

According to Fox News, the letter written by Charles J. Harder read, “We write concerning the false and defamatory statements published by Lawrence O’Donnell and NBC Universal.”

“These statements are false and defamatory, and extremely damaging. The only borrowers under these loans are Trump entities, and Mr. Trump is the only guarantor. Numerous documents for each of these loans are also recorded, publicly available and searchable online. Thus, actual malice can easily be proven based on your reckless disregard of the truth and unreasonable reliance on an alleged ‘source’ who you will not even identify in your story and likely is seeking to mislead you and the public for political reasons or other ulterior motives.”

“Demand is hereby made that Mr. O’Donnell and NBCU immediately and prominently retract, correct and apologize for the aforementioned false and defamatory statements.”

Harder wrote, “Failure to do so will leave my clients with no alternative but to consider their legal options which could include immediate legal proceedings against Mr. O’Donnell and NBCU.”

President Trump tweeted about O’Donnell’s story, “The totally inaccurate reporting by Lawrence O’Donnell, for which he has been forced by NBC to apologize, is NO DIFFERENT than the horrible, corrupt and fraudulent Fake News that I (and many millions of GREAT supporters) have had to put up with for years. So bad for the USA!”

Do you think O’Donnell should be held accountable for his false report? Is an apology enough?