This piece was originally published on Just Security, an online forum for analysis of U.S. national security law and policy.

President Donald Trump’s orientation toward Russia has become a central mystery of his presidency. He has demonstrated a strange affinity for Russian President Vladimir Putin. He has also signaled openness to advancing Russian strategic goals that have long been considered anathema to American national security interests and those of close U.S. allies. Further, Trump has rejected and resisted intelligence products and briefings that challenge his Russia assumptions.

Special counsel Robert Mueller’s counterintelligence investigation related to Russian active measures is probing suspicious contacts between Russian intelligence and a number of people in the Trump campaign or otherwise in his orbit. What’s more, Trump’s mystifying behavior and questionable campaign contacts have made the unthinkable thinkable: Is the president of the United States a witting or unwitting agent of Russian intelligence?

One of Trump’s most aberrant and alarming behaviors has been his repeated efforts to engage in unaccompanied conversations with Putin. Former National Security Council staff have raised alarm bells about those practices, reminding the president that it is in U.S. national security interests to have people on the U.S. side with a record of these interactions so that the meetings cannot be mischaracterized by the Russians, and so NSC staff can advise the president in real time if Putin is seeking to extract an unwise commitment. And it has intensified Democrats’ suspicion of Trump’s motives.

Democrats are now poised to scrutinize Trump’s two-hour private meeting with Putin in Helsinki on July 16, a meeting he resisted disclosing. Without other meeting participants on the U.S. side, the language translator will be at the eye of the storm. As the Washington Post notes, “Trump’s interpreter, Marina Gross, could be seen emerging from the meeting with pages of notes.” Director of National Intelligence Dan Coats told reporters he was not in a “position to understand fully or talk about” what happened in Helsinki. Underscoring the risks of one-on-one meetings, the most information publicly available about their interaction comes from a Russian document published by Politico.

Under its new chair, New York Rep. Eliot L. Engel, the House Foreign Affairs Committee formed an investigative subcommittee (a recommendation made on Just Security here) that is now led by California Rep. Ami Bera. Engel signaled that committee investigators will seek State Department records of Trump’s encounters with Putin, including the closed-door meeting with the Russian leader in Helsinki last summer. Last September, under Republican leadership, the committee rejected legislation seeking the Helsinki notes. On the Senate side, a similar request by Democrats in August was also rebuffed. Per Engel: “It’s been several months since Helsinki and we still don’t know what went on in that meeting. It’s appalling. It just makes you want to scratch your head.”

Broadly speaking, executive privilege is “an assertion of presidential authority to withhold information from a judicial or congressional proceeding in order to preserve executive branch confidentiality interests.” It is a controversial and contested doctrine of constitutional dimensions, especially in the context of a struggle between Congress and the president. The concept encompasses a number of different types of executive branch confidentiality interests. In the Russia investigation, two rationales for executive privilege would be at play in a request for the diplomatic translator’s notes: one related to relations with foreign governments and one related to the internal functionality of the executive branch.

The very first assertion of executive privilege can be traced back to a congressional demand for diplomatic communications. The Jay Treaty represented one of the greatest controversies of President George Washington’s term in office. Critics accused John Jay of having given up the store to the Brits during negotiations (including compensation for the capture and forced labor of seamen and confiscation of slaves at the Revolutionary War’s end). After Senate ratification, critics asserted the House of Representatives had “a discretionary power of carrying the Treaty into effect, or refusing it their sanction.” Thereafter, the House passed a resolution calling on Washington to provide a copy of the instructions Washington gave Jay as well as other documents related to treaty negotiations.

In response, Washington wrote:

The nature of foreign negociations requires caution; and their success must often depend on secrecy: and even when brought to a conclusion, a full disclosure of all the measures, demands, or eventual concessions, which may have been proposed or contemplated, would be deemed impolitic; for this might have a pernicious influence on future negociations, or produce immediate inconveniences, perhaps danger and mischief, in relation to the other powers. The necessity of such caution and secrecy was one cogent reason for vesting the power of making treaties, in the President, with the advice and consent of the Senate; the principle, on which that body was formed, confining it to a small number of members. To admit, then, a right in the House of Representatives, to demand, and to have, as a matter of course, all the papers respecting a negociation with a foreign power, would be, to establish a dangerous precedent.

The executive branch has thereafter extended Washington’s rationale to other national security information. As noted in a 1989 Office of Legal Counsel opinion: “The privilege was most frequently asserted in the areas of foreign affairs and military and national security secrets.” Protecting communications with foreign governments in the course of diplomatic negotiations remains a core confidentiality interest for the executive. For example, the George W. Bush and Obama administrations resisted providing information “outside appropriate Executive branch channels” about diplomatic assurances related to the repatriation and third-country resettlement of Guantanamo detainees cleared for transfer.

However, as Louis Fisher recounts, there is not a monolithic historical precedent, with examples in which the executive branch has not objected or objected but eventually relented to providing Congress with sensitive diplomatic information.

At present, per North Carolina Sen. Richard Burr, the Senate Select Committee on Intelligence is about to “push out the door” an assessment of the Obama administration’s response to Russian election interference and disinformation. It will be interesting to see how the Trump administration handled Obama’s head-of-state diplomatic communications. For example, did the Trump White House hand over transcripts of Obama’s red-phone communication with Putin in which Obama told Putin that U.S. intelligence knew about the election interference attempts and to back off?

The fact that the Helsinki meeting notes may be covered by executive privilege is not the end of the inquiry.

A second rationale for executive privilege here relates to the role of a translator. A translator’s primary job is to ensure that there are no inadvertent miscommunications in diplomatic communications. There are also subsidiary roles. A translator may create a record of the interaction so that the executive can refer back for purposes of creating due-out lists, following up on commitments made in the course of a meeting, or correcting the record if the other party to the conversation tries to mischaracterize the discussion. In addition, the president may rely on a translator for substantive and atmospheric advice. As such, translators’ notes may be covered by other components of executive privilege, including deliberative processes (shielding internal decision-making discussions) and presidential communications (shielding presidential-level conversations with advisers). The Clinton-era case In re Sealed Case (Espy) provides a sophisticated analysis of these two types of executive privilege.

However, if translator meeting notes become a source of discovery for political adversaries in Congress, then that could instill presidential wariness of translators in a manner that could undermine their utility—indeed, it could lead to decisions to rely solely on the other side’s translator, a course that also could have serious national security consequences. In fact, Trump has already jettisoned a U.S. interpreter to rely on Russia’s team and been criticized for it both because it suggests potential ill motives for secrecy and compromises the U.S. side’s ability to shape the meeting and its aftermath.

This argument is somewhat similar to an argument advanced by the Clinton administration seeking court recognition of an evidentiary privilege barring testimony by the Secret Service about its protectees. There, the courts rejected the argument, but here the translator’s role has a stronger nexus to the president’s substantive work such that deliberative process and presidential communications privileges could very much be in play.

The fact that the Helsinki meeting notes may be covered by executive privilege is not the end of the inquiry. One of the main takeaways of United States v. Nixon is that executive privilege is qualified rather than absolute. (Even the absolutist language of the state secrets doctrine articulated in United States v. Reynolds of that variant of executive privilege has been treated by some lower courts as qualified.) More recently, the congressional subpoena litigation over Operation Fast and Furious, Oversight Committee v. Holder/Lynch, reinforced the qualified nature of the privileges. Those confidentiality interests the executive seeks to shield from disclosure must be weighed against the acuteness of congressional need. And that balancing is done in a political context—the more suspicious the activity the less likely courts, commentators, and the public will be to sustain the executive’s position. Here, President Trump’s aberrant behavior on Russia—unusual campaign contacts, Putin praise, NATO alliance skepticism, desire to shield meetings with Putin from public disclosure and keep other U.S. participants out—significantly strengthens Congress’ hand.

In the medium term, the executive retains functional control of the information in dispute. Congress will either need executive, or whistleblower, cooperation. A formal legal ruling will not come, if it ever comes, until after a long process of escalation within the congressional investigation, followed by subpoena enforcement litigation. However, that fight itself will help shape the political environment. Moreover, even if the Trump administration successfully withholds provision of these notes, a future administration may come to a different determination.

At present, as congressional investigators determine their next moves— “whether that’s subpoenaing the notes or subpoenaing the interpreter or other steps”—the ball appears to be in Congress’s court to press its case.

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