In his interview with Newsmax TV on Thursday, McConnell shares the concerns he will highlight in his address.

"I spoke to this issue a year ago at the American Enterprise Institute ... and pointed out the abuses of the IRS that were happening already," he says.

"I'd been getting complaints from tea party groups about the difficulty of getting their tax-exempt status, which they're entitled to under the law. I pointed out efforts to intimidate groups into not buying television advertising that were being proposed over at the Federal Communications Commission, and other examples of executive branch efforts to quiet the voices of their critics.

"So I'm going to go back to the AEI tomorrow with what could best be described as the 'I told you so speech,' because the [Inspector General] at the IRS has confirmed that these groups were, in fact, being targeted.

"Now an investigation is underway in the House of Representatives and we'll find out who did it and who ordered it."

McConnell recently wrote an op-ed piece for The Washington Post stating there is ample evidence to suggest that the culture of intimidation in which the IRS tactics were allowed to flourish goes well beyond one agency or a few rogue employees.

"It started when the president shook his finger at the Supreme Court during the State of the Union a few years ago, and basically he has lectured them about the decision they made that relates to political free speech," he explains.

"It's not surprising. Not only did the president single out individuals in the country for a special tax, you had the Democratic members of the U.S. Senate writing to the IRS suggesting they do exactly what they ended up doing.

"There's no question that after the Democrats lost the Congress in November 2010, they turned to the bureaucracy to try to quiet their critics. We see it at the FEC, the SEC, at the Department of Health and Human Services. This was a fairly rampant effort encouraged by the most prominent Democratic elected officials in the country. And so it's not really surprising.

"I'm not suggesting here that the president picked up the phone and called IRS official Lois Lerner, but all she had to do was read the newspaper or turn on the TV to know what the president and his allies were hoping the bureaucracy would do to quiet the voices of his critics."

Asked if a special prosecutor is needed to look into the IRS targeting, McConnell responds:

"The Congress is likely to do the most responsible investigation. Any prosecutor appointed by the Justice Department would be kind of like the administration investigating itself.

"They could take that step if they chose to, but the investigation that will have the most credibility is the one conducted by the Republican House, and rather than jumping to conclusions, we need to have a complete and thorough investigation and let the facts lead us wherever they take us."

As for what solutions McConnell would propose to protect the individual rights guaranteed in the First Amendment, McConnell tells Newsmax: "The solution is to defend the First Amendment. It served us well for over 200 years and all these efforts to intimidate American citizens into not speaking up and to try to prevent them from promoting causes that they support need to stop.

"I don’t think we need to pass anything. We need to stop doing what we're doing in trying to intimidate American citizens. The president needs to accept the fact that not everybody's going to applaud what he's doing, that being criticized is part of public life, and efforts to quiet the voices of your critics always backfire, and this has backfired on him as well."

It appears that a comprehensive immigration reform bill is going to pass in the Senate. Asked if immigration legislation will be signed into law this year, McConnell observes: "We've still got about a week and a half to go on the immigration bill and I just don’t want to handicap the prospects of it clearing the Senate. It's much too early to tell."

"We still have plenty of really significant amendments, including ones that seek to strengthen the border, that have not yet been voted on. So you won't have a clear line on this issue until probably the end of next week," McConnell said."