Lies are told so freely and so frequently in Washington that most go unnoticed. But every now and then, there’s a whopper so outrageous you can’t let it pass.

Mitch McConnellAddison (Mitch) Mitchell McConnellSenate passes 0B defense bill Overnight Health Care: New GOP ObamaCare repeal bill gains momentum Overnight Finance: CBO to release limited analysis of ObamaCare repeal bill | DOJ investigates Equifax stock sales | House weighs tougher rules for banks dealing with North Korea MORE, the Senate Republican leader, uncorked one of those on the Senate floor last week. He said President Obama and the Internal Revenue Service have an elaborate plan for “declaring a war not just on (their) opponents, but on free speech itself.”

McConnell’s rhetoric was so over-the-top that the famously poker-faced Kentuckian must have struggled to stifle a grin as he voiced it. Let’s have a look.

The senator’s case is jerry-rigged around a draft IRS rule defining what constitutes political activity under section 501 (c)(4) of the Internal Revenue code. The law excuses from taxes non-profit groups which operate “exclusively for the promotion of social welfare” and employee associations which devote their net earnings “exclusively to charitable, educational, or recreational purposes.” In addition to being exempt from taxes, the groups are allowed to conceal the identities of their donors.

That language seems pretty clear, but the IRS traditionally has read the law loosely, giving the (c)(4) groups considerable leeway to engage in politics post-Citizens United. The tax agency currently has nothing precise in its regulations to differentiate between activities that are strictly political and those that have a political component but still qualify as “social welfare.”

The proposed rule seeks to change that. But even if it’s adopted, the IRS could decide to allow the (c)(4)s to engage in some political activity without jeopardizing their tax status.

More than 86,000 groups now enjoy the (c)(4) exemption. The number has grown in recent years, as political operators have created new (c)(4)s fueled by money from corporations and individuals who want to make six- and seven-figure investments in politics but stay out of the public eye.

At most, the draft rule may start to push the (c)(4)s away from partisan activity that would require disclosure if done by a political committee -- things like producing television ads indistinguishable from those candidates themselves might air. Some of the rule’s supporters hope donors who want to underwrite that sort of thing will give directly to candidates or to political action committees that operate under laws requiring donor disclosure.

Those big donors are McConnell’s real concern. He worries that they’ll put away their checkbooks rather than see their donations disclosed and that Republican candidates, who benefitted from most of the nearly $300 million tax-exempt groups spent on politics in 2012, will suffer in the bargain.

McConnell may be right about that, but his concern has nothing to do with a threat to free speech or the First Amendment.

The draft rule would not control the content or the volume of anyone’s speech. If it’s adopted, every donor to every (c)(4) organization will be able to spend whatever they can afford to influence candidates and elections – just as they can today.

The only change will be that they might have to spend in the open, where the rest of us, who also have to live with the candidates all that money helps elect, can see what they’re up to.

As is the case so often in Washington, this is all about money. The current IRS rules have made (c)(4)s a dream come true for business executives who fear that publicity about their political spending will upset customers and/or shareholders and cut into their income.

The First Amendment was never intended to protect people from such free market consequences of free speech. Its purpose is to shield speakers from government retaliation or censorship.

We have other laws, state and federal, to protect speakers from actual harassment, like personal injury or property damage, growing out of their political involvement. No one’s suggesting we jettison them.

While the First Amendment is a powerful guardian of rights, it has limits. Its guarantee of religious freedom does not allow faith-inspired activists to block the doors of abortion clinics; its promise of free speech doesn’t protect the job of an employee who cusses out the boss or shield the proverbial patron yelling fire in a crowded theatre. Freedom of the press is constrained by libel and obscenity/pornography laws; freedom of assembly does not permit protestors to camp out indefinitely in public parks or march without a parade permit.

The protections provided by the Constitution are subject to balancing tests. When it comes to the proposed IRS rule and other disclosure laws, the donor’s interest in hiding his or her political speech must be balanced against the public’s interest in knowing who is spending money to influence our votes.

The draft IRS rule isn’t perfect. As proposed, it could work to curtail activities like the distribution of non-partisan voter guides or the transportation of voters to the polls on Election Day. It needs serious scrutiny and revisions.

But it’s no threat, none at all, to the First Amendment.

Eisman is senior writer/researcher at Common Cause.