Hang glider tragedy and obstruct justice

A reader asked:

James, if you can answer without discussing the actual case involving a hang glider pilot, I would like to know how someone in his position could be charged with "Obstruction of Justice." I, as an average citizen, assume that someone like him has the right to remain silent. Why could someone be charged with obstruction of justice when I would assume that person should have the right to remain silent? I hope to read your response in a future post.

In general in an administrative process you may well have a duty to answer questions -- but those questions cannot be used against you in terms of a criminal charge, just administrative proceedings.   So if you are running, for example, a restuarant, you have a duty to answer questions of a health inspector.  Those answers can be used to revoke your right to operate a restuarant but cannot be used against you in criminal proceedings for, say, criminal negligence. 

In the case of the hang glider I understand (but have no direct knowledge) that the allegation is the hang glider operator is supposed to have destroyed documentation.  If true that certainly can qualify as obstructing justice. You cannot destroy evidence with a view to avoiding liability without running the risk of an obstruct charge.