tries
whose laws are designed to act directly on the _status_ of a slave,
and make him a freeman, and those where his master can obtain no aid
from the laws to enforce his rights.

It is to the last case only that the authorities, out of Missouri,
relied on by defendant, apply, when the residence in the
non-slaveholding Territory was permanent. In the Commonwealth _v._
Aves, (18 Pick., 218,) Mr. Chief Justice Shaw said: "From the
principle above stated, on which a slave brought here becomes free, to
wit: that he becomes entitled to the protection of our laws, it would
seem to follow, as a necessary conclusion, that if the slave waives
the protection of those laws, and returns to the State where he is
held as a slave, his condition is not changed." It was upon this
ground, as is apparent from his whole reasoning, that Sir William
Scott rests his opinion in the case of the slave Grace. To use one of
his expressions, the effect of the law of England was to put the
liberty of the slave into a parenthesis. If there had been an act of
Parliament declaring that a slave coming to England with his master
should thereby be deemed no longer to be a slave, it is easy to see
that the learned judge could not have arrived at the same conclusion.
This distinction is very clearly stated and shown by President Tucker,
in his opinion in the case of Betty _v._ Horton, (5 Leigh's Virginia
R., 615.) (See also Hunter _v._ Fletcher [Transcriber's Note:
Fulcher], 1 Leigh's Va. R., 172; Maria [Transcriber's Note: Marie]
Louise _v._ Marot, 9 Louisiana R. [Transcriber's Note: at 473]; Smith
_v._ Smith, 13 Ib., 441; Thomas _v._ Genevieve, 16 Ib., 483; Rankin
_v._ Lydia, 2 A.K. Marshall, 467; Davies _v._ Tingle, 8 B. Munroe,
539; Griffeth [Transcriber's Note: Griffith] _v._ Fanny, Gilm. Va. R.,
143; Lumford _v._ Coquillon, 14 Martin's La. R., 405; Josephine _v._
Poultney, 1 Louis. Ann. R., 329.)

But if the acts of Congress on this subject are valid, the law of the
Territory of Wisconsin, within whose limits the residence of the
plaintiff and his wife, and their marriage and the birth of one or
both of their children, took place, falls under the first category,
and is a law operating directly on the _status_ of the slave. By the
eighth section of the act of March 6, 1820, (3 Stat. at Large, 548,)
it was enacted that, within this Territory, "slavery and involuntary
servitude, otherwise than in the punishment of crimes, whereof the
parties shall ha