This moderator surely knows SE's functionality that a question is closed once enough users vote to close it, yet he rushed to close this one as he has done on several others. Few hours earlier the same moderator headlined his answer on Law Meta with "We are a democracy" (bold in original), which is ironic and at odds with his [ab-]use of this mod-privilege.
Being premised on some non-sequitur does not render a question "off-topic". Concluding otherwise would needlessly impose on the audience the requirement that users possess enough background in law to ensure that their intended post is "non-sequitur free". Furthermore, many questions involving a non-sequitur can be addressed from a legal standpoint. My answer there reflects how the post at issue is one such instance. Also a question can be on topic even if the scenario as described therein has no legal implications.
It is acceptable for users to miss legal aspects of a question and move to the next post. But suppressing posts merely because one such user happens to have mod-privileges is unacceptable.