President Trump meets with Russian President Vladimir Putin in Helsinki on July 16, 2018. (Kevin Lamarque/Reuters)

The Post recently reported on the lengths to which President Trump has gone to conceal details about his private conversations with Russian President Vladimir Putin. In one instance, Trump reportedly took the notes from his State Department interpreter following the meeting and ordered her not to reveal to anyone what had been discussed. This news has prompted calls for Congress to subpoena the interpreter and compel her to testify. But as outrageous as Trump’s conduct is, seeking information from the interpreter is the wrong response.

Trump routinely shatters norms that have guided other presidents, including norms governing meetings with foreign heads of state. A great risk of the Trump presidency is that we respond in kind, jettisoning important principles in pursuit of the truth about Trump’s misconduct. It’s understandably tempting to seek the interpreter’s testimony here, but that temptation should be resisted.

Imagine for a moment that a sitting president had similarly suspicious conversations with a foreign leader but the secret talks were in English, with no interpreter present. We would be left with no way to learn the contents of those conversations short of subpoenaing the president himself. Such a subpoena would no doubt trigger a vigorous legal challenge based on executive privilege and separation of powers. Politicians on both sides of the aisle would likely raise legitimate concerns about Congress intruding on the president’s ability to conduct foreign policy and speak candidly with foreign leaders.

The presence of an interpreter does not change this equation. If an attorney needs an interpreter to speak to her client, the interpreter obviously cannot be compelled to reveal conversations that were otherwise privileged. The same should be true in a meeting like this. The interpreter is essentially acting as the voice of the president, not as some independent third-party witness. If the president himself could not be compelled to discuss the conversation, the same must be true for the interpreter.

It’s worth noting that interpreters have a code of ethics that would strictly prohibit revealing any such confidences. The International Association of Conference Interpreters has put out a statement noting that interpreters are bound by strict obligations of secrecy and opposing any attempt to make Trump’s interpreter testify. That code of ethics doesn’t create a legally enforceable privilege, of course, although it does raise the possibility that the interpreter might feel professionally bound to refuse to testify and risk being held in contempt. And the White House would no doubt intervene, seeking to block the interpreter’s testimony on grounds of executive privilege, although it’s not clear whether a privilege claim would be upheld.

But the interpreter should not be placed in that position — not for her own sake but for the sake of all future diplomatic and foreign policy activities. It would be very hard for any diplomat or head of state to communicate frankly if they knew there was even a chance their interpreter could later be compelled to repeat their conversations.

Democrats who favor subpoenaing Trump’s interpreter must recognize they could be setting a precedent that would allow a future Republican Congress to subpoena the interpreter working for a future Democratic president. Even if there were an official record of the meeting, Congress might decide to subpoena the interpreter if it wanted to challenge the accuracy of that record. Especially in our current partisan environment, we should not want to start slipping down this particular slope.

It’s true this may leave us without a way to discover exactly what was said between Trump and Putin — which is the same position we would have been in had their private conversation taken place in English. That doesn’t mean we can never figure out what happened between the two of them. There are ways to investigate and prove misconduct without access to particular confidential communications, through other direct and circumstantial evidence. The law does it all the time.

Whether a president’s conversation with a foreign leader may remain confidential cannot turn on the happenstance of whether they speak the same language. For legal purposes, including the ability to probe the contents of any such conversation, it should be as if the interpreter were not even present. If there are grounds to challenge the secrecy of any such conversation, those challenges should be directed at the parties to the conversation themselves.

Congress may have the power to make Trump’s interpreter testify, but that doesn’t mean it’s the right thing to do. Trump may be shredding rules and norms on a daily basis, but we don’t need to let him drag us down with him. The work of all future presidents and diplomats depends on their ability to rely on the complete confidentiality of interpreters. We should vigorously investigate Trump’s misconduct — but we should leave the interpreter out of it.

Read more:

Jennifer Rubin: No president has ever been asked: Are you a Russian agent?

Max Boot: Here are 18 reasons Trump could be a Russian asset

Christian Caryl: There’s a way to know if Russia threw the election to Trump

Anne Applebaum: The Trump-Putin revelations tell us what we knew all along

Letters to the Editor: Translators and interpreters aren’t the same thing