This article first appeared on the Dorf on Law site.

It occurred to me when Comey was testifying yesterday to ask: "You were the FBI Director. You had access to all sorts of gadgets. After your first uncomfortable meeting with Trump, why didn't you wear a wire in person and record your phone conversations with him?"

That question in turn raised a legal question. Would it be legal?

Apparently yes. Washington, D.C. is a one-party consent jurisdiction, meaning that it is legal for a person to record his own conversation with someone else, even without the other person's consent.

As an article last month in Politifact explains, that means it's lawful for the president to record his conversations with others. It also works vice-versa, unless there is some federal law forbidding recording conversations with federal officials or the president in particular—but so far as I can tell, there isn't any such federal law.

As I said, I thought about this possibility while Comey was testifying, because I imagined that the White House response would be to cast doubt on Comey's version of events.

I then thought that this expectation was justified when "Predisent" Trump's personal lawyer Marc Kasowitz released a clearly unproof-read letter that cherry-picked the parts of Comey's testimony he liked—Trump himself was not under FBI investigation (at least not prior to his interference with that investigation); Comey was the leaker of what Kasowitz described as "privileged communications—while ignoring or contradicting the parts of Comey's testimony Kasowitz disliked—e.g. Trump's demand for loyalty.

The Kasowitz letter at least partly explains why Comey said that "Lordy, I hope there are tapes." Tapes would presumably vindicate Comey's entire account.

And then on Friday el Predisente tweeted that Comey's testimony provided "total and complete vindication." Trump didn't bother to contradict anything Comey said, perhaps in tacit recognition that in a swearing contest the pathological liar is at a serious disadvantage. So maybe Comey didn't need to wear a wire after all.

But that doesn't mean that others don't.

Trump's modus operandi when facing unpleasant accounts of his behavior is to deny it, to attack the character(s) of the source(s), to completely mischaracterize the account, to claim that his own behavior as described was not a big deal (e.g., "locker-room talk"), and to just claim vindication in general terms.

Wearing a wire won't protect against all of these moves, but it will protect against the first two.

Michael C. Dorf is the Robert S. Stevens professor of law at Cornell University. He blogs at DorfOnLaw.org.