John Adams echoes

Fading?
So now they're going after the supposedly treasonable lawyers who tried to get us to uphold our values and Constitutional boundaries some more. These are the faults they supposedly had, this one in particular is worth pointing out and holding in contempt.

"a) interfered with the operations of the Department of Defense at Naval Station, Guantanamo Bay, Cuba, relating to [non-citizens detained at Guantánamo]"

In so far as those operations were a legitimate detention program, I can see cause here. In so far as requesting information as to the beatings or torture or, more pressingly, the status and nature of their detentions go, which is more or less what lawyers do (summon vast reams of paper from bureaucracies like the federal government and the military detention programs), I'm not sure this is a legitimate complaint. A lawyer who wasn't interfering in that way was probably not doing their job.

Secondly, the issue is, like with the immigration law in Arizona, the principle of "reasonable suspicion" and its interpretation being somewhat different in a practical rather than a strictly legal sense. Lawyers performing the unpopular task of defending disreputable clients such as those accused (but not proven) of terrorist or hostile acts against the US government and its people will be easy enough to frame as performing some sort of interference in the national interest of safety or security, regardless of whether
1) the program of indefinite detention actually improves safety or security (indeed, it may be a source of propaganda and recruiting for our enemies owing to its hypocrisy within our legal framework, thus a potentially grave risk to long-term safety)
2) the opposition to that program through legally sanctioned channels, as conducting habeas status for detention is legally sanctioned by court rulings, is in some manner itself a form of interference.
3) "reasonable suspicion" is at all a grounds for launching investigations which might terminate or suspend the operations of legal counsel to the expense of their client, especially with this being often legal counsel appointed or approved by the government itself.

Lawyers who do in fact endanger some vital US interest might be something we could consider as treasonable, if such examples existed. But representing the Constitutional values and rights that we accord to people under our jurisdiction does not strike me as an onerous, terrible, and thus treasonable interference.

Speaking of the clients those lawyers represent... we don't seem to have the best track record in so far as finding guilty people to imprison without charges.