Josh Campbell is a CNN law enforcement analyst. He previously served as a supervisory special agent with the FBI, special assistant to the bureau's director, and is currently writing a book on recent attempts by elected officials to undermine the rule of law. Follow him on Twitter at @joshscampbell. The views expressed in this commentary are his own. View more opinion articles at CNN.

(CNN) President Donald Trump continued his assault on the Department of Justice and FBI officials probing his campaign's alleged ties to Russia this week. Trump remarkably labeled them a "disgrace" at a political rally in Evansville, Indiana, and insisted instead the investigation is "illegal."

Lost in the President's relentless campaign to undermine our institutions of justice is the realization that Trump and his enablers are actually making it harder to hold agencies like DOJ and the FBI accountable when they do in fact make mistakes.

Trump is constantly crying wolf, and it is to the detriment of good governance.

Each new day seemingly brings some fresh line of attack against those entrusted with upholding the rule of law. Ostensibly the goal is to continue to undermine the credibility of law enforcement, in order to discredit whatever final conclusions are reached by the ongoing special counsel investigation into alleged Russian interference in the 2016 presidential election.

Tuesday, the President set off a political firestorm by questioning the professionalism of the men and women at the DOJ and the FBI. "Report just out: 'China hacked Hillary Clinton's private Email Server,'" Trump tweeted. "What are the odds that the FBI and DOJ are right on top of this?" he continued, adding that the credibility of the agencies would be "forever gone" if they failed to fully investigate the matter.

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