Editor's note: Rand Paul, a Republican, is a U.S. senator from Kentucky.
(CNN) -- The Internal Revenue Service has admitted that it targeted groups with "tea party" or "patriot" in their names. We've since learned that a wider array of groups concerned about spending, debt, high taxes, government growth, the Constitution, the Bill of Rights -- basically any conservative or libertarian issue you can name -- was targeted.
President Obama said Monday that he was "outraged" over the IRS' behavior. He said that those responsible should be held "fully accountable." I wonder when that will happen?
On Wednesday, the president requested and received the resignation of Acting IRS Commissioner Steven Miller -- but that is not enough. The executive branch has been aware of this scandal for nearly two years and now, only as a result of massive public pressure, the administration has found a scapegoat.
The president did not announce that Miller was responsible, and we still don't know who came up with the idea to target the tea party. We have not been told whether Obama administration officials knew about the discrimination and if they allowed it to continue when they found out. Forcing out Miller is not the end of this scandal.
Holding the guilty parties accountable is just the first step. But if the handling of the attack in Benghazi, Libya, is any indication, there are no guarantees this will happen.
The IRS is under the president's jurisdiction. He needs to fully recognize the gravity of these charges.
The IRS targeting citizens for political reasons is not simply another Washington scandal. At issue is something that strikes at the very heart of who we are as a people, what we believe as Americans and what this country has always stood for.
The First Amendment was written to protect many different types of expression. But the Founding Fathers' primary concern -- and a first principle for every generation of Americans that followed -- was the protection of political speech. Apparently, the IRS was even targeting people who criticized how the country was being run.
Protecting citizens' right to speak out against their government has always been an integral part of what separates us from tyrannical regimes. What the IRS did is how the KGB used to target dissidents. It is how they deal with troublemakers in China.
It is not how we treat American citizens. Our Constitution guarantees it.
This week, I introduced a Senate Resolution condemning the IRS' actions and calling for a full investigation into how the agency infringed upon the First Amendment rights of those targeted.
Democrats put a hold on my resolution.
We have learned that some officials knew about these indiscretions long before the recent denials. We wanted to investigate to find out who knew what, when, and for how long.
We have learned that some tea party groups had unduly long wait times for tax-exempt status. Some eventually withdrew their applications out of frustration.
In my home state of Kentucky, a 9/12 group filed for 501(c)(4) status in December of 2010. It received its first correspondence almost immediately, saying there would be a determination within 90 days.
Fourteen months later, the IRS requested answers to 30 questions with sub-bullets -- 88 total separate inquiries -- and gave only a two-week period to comply.
The Kentucky 9/12 Project's Eric Wilson estimated that it would have taken 5,000 pages to respond.
Eventually, the IRS granted granted this group tax-exempt status -- after well over a year. We wanted to find out why they had to wait. We wanted to find out what groups, and how many, might have been victims of political discrimination.
We wanted to ask for an independent authority to investigate and seek criminal charges against those who were involved in targeting Americans for their political views. We wanted to determine if the White House was aware and failed to take action.
This is not about Republican vs. Democrat or conservative vs. liberal. It is about arrogant and unrestrained government vs. the rule of law. Imagine if the IRS had targeted liberal or progressive groups under the Bush administration. The First Amendment cannot be renegotiated depending on which party holds power.
The power to tax is the power to destroy. These allegations concerning the IRS remind us yet again of the inherently destructive nature of leviathan. With Obamacare adding staff and hundreds of millions to the budget of the IRS, the new and intrusive powers granted to our nation's revenue collection service were worrisome enough. We should use this recent abuse of power as an opportunity to rein them in.
Each congressman and senator, and even the president, took an oath to uphold and defend the Constitution. It is now upon us to determine if the IRS intentionally trampled the First Amendment rights of Americans who dared to dissent.
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The opinions expressed in this commentary are solely those of Rand Paul.