You implied it was okay for the teacher to talk out his ass about the 5th amendment because someone needs to tell kids to "spit in the face of authority."
Fact: There is a 5th Amendment right against self-incrimination.
Fact: The kids have a right to not fill out the survey.
Debatable, but not a settled point either way: Whether or not the aforementioned 5th Amendment protection specifically applies in this situation.
As you can see from all the other discussion on this HN forum, whether or not the 5th Amendment comes into play here is subject to debate, and it's hardly an unreasonable position to take, to suggest that it does apply. Stating that is not even close to "disinformation" or "talking out of his ass".
It's also important to note that these kids weren't taking a class to prep for the bar exam, and you wouldn't expect the same level of precision regarding this topic, from this teacher, as you would from a class and a teacher focus on that topic specifically. To some extent, ALL middle-school teachers and high-school teachers, and some college professors, are "talking out their asses" when teaching about the Constitution, and history related to laws and legalities in this country... but we don't run around accusing them of spreading disinformation for teaching at the level of generalities.
So I am only implying that it's OK for the teacher to "talk out of his ass" to the extent that everybody talks out of their ass most of the time. So I guess I'd say you're being overly pedantic, IMO.