Three years after President Obama said wrongdoers involved in the IRS political persecution scandal should be held "fully accountable," no one has been held accountable. Aside from Lois Lerner -- whom Obama's Department of Justice refuses to prosecute -- no one exemplifies the wrongdoing at the IRS more than its current commissioner, John Koskinen.

The House Judiciary Committee will vote this week on whether or not to impeach Koskinen; they should do so and the full House should follow and then the Senate should convict him, if there's any rule of law left in America.

Three years after the IRS admitted to targeting conservative organizations, the targeting continues unabated. But now, the targeting operation is even more sinister.

From 2009 to 2013, the IRS singled out conservative non-profit groups seeking tax-exempt status and subjected them to excessive delays lasting years, and intrusive questionnaires. In many cases, those questionnaires helped fuel IRS audits of individuals and small businesses. As the president of the nation’s largest grassroots tea party organization, I can attest to the devastating impact of the targeting scandal.

Once it became clear in 2013 that our worst fears had been correct and that the IRS had been violating our First Amendment rights, hundreds of organizations attempted to join a class-action lawsuit. But until this week, the IRS refused to disclose the list of organizations it had targeted. Only after a federal judge turned up the heat on the IRS to release the list did the agency provide the information.

Don’t miss this: The IRS stubbornly refused – for three years! – to provide that basic information, which left groups in the dark about whether or not they could even seek damages. The IRS was thus able to further victimize the victims of its targeting scandal, making it impossible for the legal case to advance.

The issue at hand is by no means trivial. The right to seek redress from the government for grievances is such a fundamental right that undergirds all other rights – and that’s precisely why it is included in the First Amendment.

The IRS’s 2013 admission of guilt marked the beginning of a new chapter in the IRS’s targeting playbook. This new phase is even more shocking because it has been conducted in plain sight – with the public, the courts, and Congress all scrutinizing the agency.

Far from being chastened after getting caught red-handed in the first targeting scandal, the IRS seems almost emboldened to continue the targeting after getting away with flouting the law.

During the initial phase of targeting, the IRS went to great lengths to cover its tracks. Records were purged, files were deleted, emails were mysteriously lost, and, incredibly, computer servers allegedly vanished into thin air.

In the first phase, the IRS was so conscious of the severity of its wrongdoing that IRS employees – across a broad spectrum of seniority – engaged in a massive attempt to cover up the agency’s wrongdoing.

Today’s IRS targeting scandal is entirely different because the agency no longer bothers with the cover-up. The IRS’s in-broad-daylight targeting is reminiscent of a childhood dare: “Yeah, we target conservatives. And just what are you going to do about it?”

To see the IRS’s cavalier attitude on display, one need only look at how the IRS has refused to cooperate with the Congressional investigations. Rather than comply with the investigations, the IRS has consistently slow-walked requests, “lost” pertinent information, and outright lied to members of Congress and the investigators. IRS Commissioner John Koskinen is the worst offender and has lied shamelessly to Congress about nearly every aspect of the targeting scandal.

Confidence in the federal government is at an all-time low. And is it any wonder? It is deflating to our nation’s morale that the IRS – arguably the most feared federal agency – can trample on our First Amendment protections, defy Congress, and make a mockery of our system of justice with impunity.

In an effort to restore accountability to an agency gone wild, House Oversight Committee Chairman Jason Chaffetz recently introduced an impeachment resolution to remove John Koskinen from his position for his role in perpetuating the scandal and hampering the investigations.

Impeachment is, of course, an extraordinary measure and should be reserved only for the most egregious misconduct. In Federalist No. 65, Alexander Hamilton explained that impeachment is appropriate to address “those offenses which proceed from the misconduct of public men, or, in other words, from the abuse or violation of some public trust.”

Mr. Koskinen’s disregard for the rule of law meets Hamilton’s exacting requirements for impeachment. In fact, Koskinen’s misconduct demands impeachment if we are to restore the public trust and move past the IRS’s wholesale disregard for the Constitution.