Thank you for your thoughtful comments on civil disobedience
and non-violence, concepts which, it seems to me, are deserving
of further thought.  Your observation is undeniably correct,
that a person violating the fugitive slave act, is likely to
identify him or herself with a protest movement.  He/she may
be subscribing not primarily to his/her own ethos, but to the
ethics of a group. It's not the individual then, but the group
which sets itself in opposition to the state, a stance which
taken to its logical conclusion will lead to emigration (as
with the Quakers), or to revolution (as with the French Jacobins),
or to secession (as with the American South).

All societies are constituted by verbal formulas, by laws,
on which they depend for their existence.  They cannot survive
disregard of the laws. Where such disregard is by the individual,
it is stigmatized and punished as crime. When such disregard of
the laws is corporate, it is stigmatized and punished as treason.

Thoreau's "civil disobedience" is an appeal to individual
conscience, not to group or social consensus. He wrote that the
person who is marching out of step with his peers is listening
to the beat of a different drummer. Thoreau's civil disobedience
is far from non-violent. It extends even to revolution and
mutiny by force. Witness his endorsement of John Brown.

I'm too ignorant about Gandhi to comment; but Martin Luther
King's reference to inspiration by Thoreau is incongruous
(as is his middle name). Thoreau never said: WE shall overcome.
Luther may have had it both ways.  He is quoted (probably
erroneously):

"Hier stehe ICH, ICH kann nicht anders, Gott helfe MIR. Amen."

More accurate is the following:

"...wenn ich nicht durch Zeugnisse der Schrift und klare
Vernunftgründe überzeugt werde; denn weder dem Papst noch
den Konzilien allein glaube ich, da es feststeht, daß sie
öfter geirrt und sich selbst widersprochen haben, so bin
ich durch die Stellen der heiligen Schrift, die ich angeführt
habe, überwunden in meinem Gewissen und gefangen in dem
Worte Gottes. Daher kann und will ich nichts widerrufen,
weil wider das Gewissen etwas zu tun weder sicher noch
heilsam ist. Gott helfe mir, Amen!"
 
But Luther also wrote: "Ein feste Burg ist UNSER Gott."

Martin Luther King was a community organizer who sensed a
readiness in his community to take non-violent action for
a cause in which he believed. Although logically, refusal
to move to the back of the bus, and demanding to be served
at a segregated lunch counter is civil disobedience, the
aspect of potential "violence" is so slight as to be
inapparent. Non-violent protest is effective only in a society
ready to accede. Elsewhere it is crushed. Consider contemporary
Libya, Syria, Yemen ...

Just now I read the Wikipedia article on Civil Disobedience;
found it very informative and far more complete than my comments.
My conclusion: that civil disobedience is the "tip of the iceberg"
of broad and deep and universal conflicts between the individual
and society and between societies....