Don Jr. Photo: Jim Watson/AFP/Getty Images

As shoe after shoe after shoe keeps dropping about the Trump Tower meeting Donald Trump Jr., Jared Kushner, and Paul Manafort had with a Russian lawyer and other questionable intermediaries, there has been a quiet but significant effort by prominent legal minds to defend, or at least be skeptical of, the whole affair. The thrust of these counterarguments is that the main characters did nothing wrong because the law simply doesn’t penalize anything that happened at the meeting.

The defenses run the gamut: The Trump team couldn’t have broken campaign-finance laws because seeking and receiving damning materials on a political adversary is what campaigns do all the time, so federal law doesn’t apply. Or, if the law does reach what transpired at the meeting, the promised “dirt” on Hillary Clinton isn’t the type of in-kind contribution or “thing of value” that federal law forbids foreign nationals from making. Or, if the damaging information does count as an illegal campaign contribution from a foreign national, the penalties would only be civil in nature — which means Robert Mueller, the Russia special counsel, can’t just prosecute Trump Jr. or his associates over what happened at that fateful June 2016 gathering.

By far the most intriguing of all these defenses is the suggestion, advanced by First Amendment expert and UCLA law professor Eugene Volokh, that Trump Jr. and crew were merely exercising their constitutional right to solicit and receive a campaign boost from Natalia Veselnitskaya, the Kremlin-linked attorney who requested the meeting. And that she may also have been acting within her rights to share the Clinton dirt with Trump’s inner circle. As if there’s somehow a free-standing, free-speech right to exchange opposition research, no matter the nationality of the source. And the Constitution would suffer if we criminalize these acts.

Volokh’s arguments and hypotheticals are thoughtful, compelling even: “If the Clinton campaign heard that Mar-a-Lago was employing illegal immigrants in Florida and staffers went down to interview the workers, that would be a crime,” he writes as one of his examples. A Slovakian student temporarily in the U.S., he writes in another, would similarly be forbidden from sharing potentially explosive information about Trump’s dealings in her home country. These and other scenarios are meant to illustrate how the federal ban on foreign nationals making election-related contributions — including “anything of value” to a campaign, which would encompass the Clinton dirt — would sweep far too broadly. And when a ban lends itself to such a “substantially broad” reading, Volokh explains, that means the ban itself is unconstitutional on its face.

But Adav Noti, an attorney with Campaign Legal Center, isn’t convinced. His organization filed a complaint on Thursday with the Federal Election Commission and the Department of Justice alleging that the Trump campaign effectively solicited an illegal campaign contribution by procuring the incriminating Clinton evidence from Veselnitskaya. Noti told me in an interview that most of the hypos Volokh laid out in his article “aren’t covered by the statute” because the law already contains an exception for volunteer services to a campaign — information that is offered voluntarily and that you otherwise can’t ascribe value to.

But opposition research by a person flying in from Moscow at no cost to the campaign that the campaign actively sought can indeed be very valuable. And, if it’s part of a larger, coordinated effort by a foreign power to sway an American election, a scheme to obtain it would be largely distinguishable from, say, undocumented workers dishing to the Clinton camp for free on shoddy working conditions at a Trump property.

Bob Bauer, an election-law expert who has written extensively on the campaign-finance implications of Trump’s flirtations with Russia, acknowledged in a Friday post on the blog Just Security how the federal ban on foreign-national contributions might run into First Amendment problems if the right facts come along. But we’re not dealing with those facts right now. In his view, everything that has come out from the Trump campaign vis-à-vis Russia is an entirely different animal. “A court would likely go out of its way to uphold the law in a case where, as alleged against the Trump campaign, a candidate and his organization enters into a systematic understanding with a foreign government to assist its bid to win the presidency,” Bauer wrote.

In other words, what we’ve seen so far in the recent onslaught of revelations about Trump Jr. and his wish to get an assist from Russia is analogous to the kind of conduct that courts have already said falls outside the scope of the First Amendment. In Bluman v. FEC, a case Noti litigated and won, a three-judge district court reaffirmed the principle that prohibiting foreign nationals from spending money in the electoral process is perfectly consistent with our constitutional ideals. The court said:

It is fundamental to the definition of our national political community that foreign citizens do not have a constitutional right to participate in, and thus may be excluded from, activities of democratic self-government. It follows, therefore, that the United States has a compelling interest for purposes of First Amendment analysis in limiting the participation of foreign citizens in activities of American democratic self-government, and in thereby preventing foreign influence over the U.S. political process.

That was written by U.S. Circuit Judge Brett Kavanaugh, a conservative the Trump administration has been eyeing for a promotion to the Supreme Court. The high court, for its part, didn’t even bother hearing an appeal over the case; it just affirmed the ruling summarily with no dissenting opinions. All of which suggests that other judges would follow suit if presented with the Trump Tower scenario: a meeting where no actual money may have changed hands, but where something more nefarious, coordinated, and potentially criminal may have taken place. There’s yet more to come.

Courts have a way of salvaging perfectly constitutional laws if they have to, limiting their analysis to the specific fact patterns before them. Since the documented Russian connections to the Trump campaign is unlike anything this country has seen, it’s easy to see how the First Amendment wouldn’t stand as an obstacle if it were shown that there was a coordinated attempt to strike at the core of American self-government.