President Trump is under fire once again this week for asking Attorney General Jeff Sessions to “stop this Rigged Witch Hunt right now, before it continues to stain our country any further.”

Democrats were quick to respond, including Rep. Joe Kennedy, D. Mass, who tweeted, “Mr. President, what you call a stain, we call a justice system standing strong for our democracy. Your fear of this investigation will not bring it to an end.”

But the president makes a valid argument. Why? Because for years many investigations that were led by the DOJ and FBI have been anything but fair. Allow me to explain.

Like an inflatable inner tube with a small leak, special counsel Robert Mueller and his team continue to lose credibility by the day. Whether it's the Justice Department or FBI withholding information, or conflicts of interest and political biases (13 of 17 people on Mueller’s team have registered as Democrats), the investigation into “collusion” has nevertheless morphed into a witch hunt determined to tear apart a country and bring down a presidency.

Playing politics during an investigation, twisting the facts, withholding information, deploying spies or conducting carefully orchestrated press conferences are just some of the tactics the FBI and DOJ have been using for a long time. Like big game hunters, they set their sights on powerful elected officials. If they can’t prove a crime, they’ll create one. And as effective communicators, they’re always controlling the narrative.

For example, on July 29, 2008, Sen. Ted Stevens, R-Alaska, was indicted in a political corruption case for violating ethics laws and failing to properly report gifts. A few months later, Stevens was found guilty. Calls for his resignation began immediately after the conviction, and President Barack Obama even jumped on the bandwagon, saying that Stevens needed to resign to “put an end to the corruption and influence-peddling in Washington.”

One month later, Stevens lost re-election in an embarrassing defeat. But on April 7, 2009, federal Judge Emmet G. Sullivan voided the convictions and dismissed the indictment citing prosecutorial misconduct.

And in 2012, a special counsel report was released that said, “The investigation and prosecution of U.S. Senator Ted Stevens were permeated by the systematic concealment of significant exculpatory evidence which would have independently corroborated Sen. Stevens’ defense and his testimony, and seriously damaged the testimony and credibility of the government's key witness.”

That’s right, the federal prosecutors withheld evidence during the trial to fit their narrative that Stevens was a corrupt politician. But the damage was done. Stevens was no longer a senator.

Here’s another example. In 2011, U.S. Attorney Ron Machen began investigating D.C.'s Democratic Mayor Vincent Gray for campaign-related corruption. The investigation dragged on for four years. In a stunning move, exactly one month before the D.C. primary election, Machen invited reporters into his office where he laid out a case against Gray, framing him as a corrupt politician. The takeaway? An indictment was forthcoming.

One month later, Gray lost his re-election in an embarrassing defeat. One year after Gray’s defeat, Machen quietly stepped down from his post. A few months later, after reviewing the nearly five-year investigation, the new U.S. attorney closed the case. But the damage was done. Gray was no longer mayor.

The case of former Gov. Rod Blogojevich, D-Ill., is yet another example of DOJ and FBI abuses. On Dec. 10, 2008, then-FBI Director Robert Mueller authorized a ruthless and unnecessary predawn raid to arrest Blagojevich in front of his two terrified young daughters, threatening to break down the door if they didn’t answer. A few hours after the arrest, the fame-hungry U.S. Attorney Patrick Fitzgerald (a best friend of former FBI Director James Comey) held a press conference to control the narrative and label Blagojevich as a corrupt politician. One month later, Blagojevich was impeached and removed from office.

During the trial, prosecutors suppressed evidence and twisted the law to fit their political agenda. In the end Blagojevich was sentenced to 14 years in prison for fundraising violations, a routine practice in politics.

If they could take down the governor of the fifth-largest state, why not set their sights on something much higher? And they have.

During an appearance on Fox News back in May, Patti Blagojevich said, “I see that these same people that did this to my family, who secretly taped us, twisted the facts, perverted the law which put my husband in jail, these people are trying to do it on a larger scale (to Trump).”

And former White House Communications Director Anthony Scaramucci said during a segment on "Justice with Judge Jeanine" a few days later that “what happened to [Blagojevich] was sort of the fire starter for what ultimately they ended up doing to candidate Trump and President Trump, because they were getting away with so much latitude and prosecutorial overreach and basically weaponizing these agencies and using them as political instruments to take out their enemies.”

Talk about prosecutors “weaponizing agencies” to “take out their enemies" sounds more like Cuba or Venezuela, not the U.S.

“The rule of law is under assault in America,” as Blagojevich wrote in a Wall Street Journal op-ed from behind bars. “It is being perverted and abused by the people sworn to enforce and uphold it. Some in the Justice Department and FBI are abusing their power to criminalize the routine practice of politics and government.”

And he’s right. “Drain the swamp” is more than a catchy phrase to President Trump. It’s a call to action. Let’s support the president and Make America Great Again.

Mark Vargas (@MarkAVargas) is a tech entrepreneur, political adviser, and contributor to the Washington Examiner's Beltway Confidential blog.