(Bloomberg) -- Attorney General William Barr said the decision to open a probe of then-candidate Donald Trump’s campaign in 2016 was “baseless” and relied on “flimsy” evidence that sets a poor precedent for the U.S.

Barr, in his first interview since the Justice Department’s inspector general released his report on the origin of the investigation, said there was insufficient evidence to open a probe, contradicting the key finding of Monday’s report. He also signaled that the bar to do so should be higher to justify using law enforcement and intelligence agencies to look into a presidential campaign.

“Our nation was turned on its head for three years based on a completely bogus narrative that was largely fanned and hyped by an irresponsible press,” Barr said in an interview Tuesday on MSNBC. “When you step back here and say, ‘What was this all based on,’ it’s not sufficient.”

The report by Inspector General Michael Horowitz said the Federal Bureau of Investigation acted properly when it opened its probe in 2016 in order to “obtain information about, or to protect against, a national security threat or federal crime.” In a conclusion seized upon by the president’s supporters, however, Horowitz also cited 17 “significant inaccuracies and omissions” in obtaining Foreign Intelligence Surveillance Act warrants against a former Trump campaign aide.

The top U.S. law enforcement officer said presidential campaigns are frequently in touch with foreign people and that there are regularly signs of illegal foreign money coming into those campaigns. But, he added, “we don’t automatically assume these campaigns are nefarious and acting in league with foreign powers.”

Barr gave a harsh assessment of the FBI’s role in the probe, saying its behavior was “inexplicable” and “intolerable.” He reiterated his view that a separate probe still underway by U.S. Attorney John Durham will be more comprehensive.

To contact the reporter on this story: Bill Faries in Washington at wfaries@bloomberg.net

To contact the editors responsible for this story: Bill Faries at wfaries@bloomberg.net, Kevin Whitelaw

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