I think that you mean Lori Berenson and, no, she was convicted of terrorism not treason. I also looked up the 1890 Mississippi Constitution and, son of a gun, it's right there. Anyone who dares to make war on Mississippi or give aid and comfort to her enemies can be convicted of treason against Mississippi. Provided there are two witnesses, of course. That begs the question of how does one war against a state without warring against the United States and would that mean that anyone waging war against the U.S. could be convicted of treason in Mississippi? Still, whatever floats their boat, I guess.
Actually with Brown I think it was the other way around. The Buchanan government wanted absolutely nothing to do with trying him because of fears that such a trial would have divided the Congress, and were more than happy to allow Virginia the honors. Which Virginia did, with efficiency and expediency.
Lori was actually tried and convicted of treason and then several years later that verdict was nullified by a higher court. She still of course languishes (quite rightly in my view) on terrorism charges. The nullification was not based on the charge but rather the circumstances of her "trial". Why the terrorism conviction was not nullified as well considering it was the same trial is beyond me...we are talking about Peru here..LOL....I would assume she is political capital to be traded for humanitarianism reasons at some point down the road.
I think I meant almost the same thing on Brown except that I think the Buchanan government was quite willing to be rid of him. Otherwise why did they send Federal troops to Harper's Ferry?