Special counsel Robert Mueller is now investigating whether President Trump has committed obstruction of justice, the Washington Post reports. This news should shock precisely no one: Mueller’s mandatespecifically authorizes him to investigate obstruction of justice allegations arising out of his probe. But the report underscores the seriousness of the obstruction allegations against Trump — and the strength of the evidence already amassed.

In a nutshell, the case against President Trump consists of the following: The President intimated to then-FBI Director James Comey in February that Comey ought to shut down the bureau’s investigation of former Trump national security adviser Michael Flynn. When Comey rebuffed him, President Trump sought to enlist Director of National Intelligence Daniel Coats in an effort to stop the Flynn probe.

Making matters worse, President Trump then fired Comey and said publicly that the firing was related to the Russia investigation — a statement that might be interpreted as an implicit threat to Comey’s replacement that he should bring the probe to a halt if he wanted to keep his job. Whether or not any of these actions would amount to obstruction in isolation, they sum up to a course of conduct that might very well place President Trump on the wrong side of the criminal law.

Trump may be shielded from criminal indictment by virtue of his status as president, and he may remain shielded from impeachment by virtue of the fact that his own party controls both chambers of Congress. On the law, though, the argument that Trump is guilty of obstructing the FBI’s Flynn probe is quickly gathering steam.

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