Could the president’s tweets be building his own case for impeachment?

The Trump presidency will go down in history for many reasons. Among them: He’s the first president to use Twitter in such a prolific – and provocative – manner. The president continues to shock and surprise with his unfiltered utterances.

Stirring up social media has long been central to his persona. Twitter is the president’s mouthpiece of choice for personal affronts, puffery and presidential insults. And it’s also his method of choice for continually putting his foot into his mouth.

A far cry from FDR’s popular “fireside chats,” Trump’s reliance on Twitter is more than just a PR nightmare. It may very well be what sinks him in the end.

How they could be used against him

Social media posts are fair game for prosecutors. In fact, they often serve as key evidence, particularly when the defendant’s intent or knowledge is at issue. Who better to support the prosecution’s case than the defendant himself, in his own words?

It’s therefore not surprising that the Mueller probe is taking a close look at Trump’s tweets, according to sources close to the investigation.

Trump has used Twitter to repeatedly rail against the Mueller probe as well as Attorney General Jeff Sessions and the entire Justice Department. Last fall, when news broke that George Papadopoulos (a former advisor to the Trump campaign) was cooperating with the investigation, Trump immediately tweeted that Papadopoulos was a liar. More recently, he implied that the Justice Department was meddling in midterm elections by indicting two Republicans (who also happened to be Trump supporters) for insider trading and misuse of campaign funds.

Perhaps the biggest smoking gun, however, was the tweet about Michael Flynn, his former national security advisor who pled guilty to making false statements to the FBI. When Flynn initially came under the scrutiny of former FBI Director James Comey, Trump allegedly pressured Comey to drop the investigation. Comey refused.

His subsequent firing is a key issue in the Mueller probe. If Trump fired the man to sink the investigation into Flynn – an obstruction of justice – it would be tremendously helpful to have evidence that Trump knew Flynn was guilty of wrongdoing. Last winter, Trump himself supplied that evidence, tweeting, “I had to fire General Flynn because he lied to the Vice President and the FBI.”

After this tweet’s significance was spelled out in the media, Trump’s personal lawyer at the time, John Dowd, made the dubious claim that he wrote it. The Mueller investigation will no doubt uncover who actually authored the tweet.

It wouldn’t be the first time

Presidential tweets may play a central role in the obstruction investigation. They may even feature prominently in the final report Mueller issues to Congress.

If so, it wouldn’t be the first time Trump’s tweets have been used against him. Shortly after he took office, the Ninth Circuit Court of Appeals cited a controversial tweet (characterizing a broad sweep of nations as “dangerous”) in overruling Trump’s travel ban on Muslim countries. A D.C. Appellate Court used Trump’s tweets against him in the case addressing Obamacare subsidies. And last January, a federal judge referenced a presidential tweet in his ruling against the validity of Trump’s DACA reversal.

A single tweet, in isolation, perhaps wouldn’t be enough to support the case for impeachment. But together, they may very well point to a pattern of intimidation and obstruction. By tweeting so freely and frequently, Trump has provided Mueller with a treasure trove of potential evidence. And he shows no signs of stopping anytime soon.