Any one of the president’s single acts against the FBI director could be written off by reasonable people, but adding on top a desire to lock him up should tip the scales.

Has President Donald Trump just tipped the scales in favor of concluding that he has obstructed justice?

Recent reporting by The New York Times and CNN that Trump sought to direct the Department of Justice to prosecute Hillary Clinton and James Comey is an alarming violation of presidential norms, and it may also cross the line into illegal conduct.

While a directive by a president to prosecute a political rival like Clinton is highly unusual and inappropriate, it is the order relating to Comey that is most likely to amount to criminal behavior.

The president, as head of the executive branch, leads the Department of Justice and all other components of the executive branch. As such, the law does not prohibit him from suggesting or even directing DOJ to use its resources to investigate a potential crime.

To avoid the appearance of partisanship in the use of this power, however, norms have emerged in which DOJ and the White House discuss cases only at a high level, usually relating to policy decisions and priorities as opposed to charges in individual cases. Instead, the attorney general is entrusted to exercise his duties with independence, free from political interference by the president. This independence is important to ensure the reality and the perception that case decisions are made based on facts and evidence, and not on political considerations.

Directing DOJ to investigate Clinton for possible criminal conduct violates these norms by involving the president in a particular case. It becomes especially jarring when the target of such an investigation is the candidate who opposed the president in the election that put in him office.

But this problem is compounded when it comes to Comey. In addition to creating the appearance that charges are being sought to even the political score for Trump, prosecuting the former FBI director could also be motivated by a desire to discredit him as a witness in the special counsel Robert Mueller’s investigation into links between the Trump campaign and Russia to interfere in the 2016 presidential election. If so, this directive to prosecute Comey could be evidence of obstruction of justice by Trump.

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