If we go by Webster Dictionary "rubric"
well
1.) "the betrayal of a trust : treachery"
---> CHECK
2.) the offense of attempting by overt acts to overthrow the government of the state to which the offender owes allegiance or to kill or personally injure the sovereign or the sovereign's family
---> not quite there.....he committed the act and then he surrendered. Though one could argue that the so-called "lawyers" who threw petals on him seem to take their jobs as 'public defenders' a bit too seriously ---to the point that they are willing to justify an act of murder because they saw his action as 'noble'
that was irresponsible of them, but they weren't necessarily representative of the views of people in the entire country.
when push comes to shove -- murderers and their supporters/apologists such as the ones in this case, they are treacherous people.