During the period of 1898 to 1903 the U.S. Army was protecting slave owners and traders in order to win their peace especially with the Moro tribes of Sumar.
Here is one just one case...
[Supreme Court of the Philippine Islands (A United States Colony)
The judge below quotes the Bill of Rights of the Philippines contained in the Act of Congress of July 1, 1902, declaring that ' neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist in said Islands.' This constitutional provision is self-acting whenever the nature of a case permits and any law or contract providing for the servitude of a person against his will is forbidden and is void. For two obvious reasons, however, it fails to reach the facts before us: —
"First. The employment or custody of a minor with the consent or sufferance of the parents or guardian, although against the child's own will, cannot be considered involuntary servitude.
"Second. We are dealing not with a civil remedy but with a criminal charge, in relation to which the Bill of Rights defines no crime and provides no punishment. Its effects cannot be carried into the realm of criminal law without an act of the legislature,"
and also that: —
"To sum up this case, there is no proof of slavery or even of involuntary servitude, inasmuch as it has not been clearly shown that the child has been disposed of against the will of her grandmother or has been taken altogether out of her control. If the facts in this respect be interpreted otherwise, there is no law applicable here, either of the United States or of the Archipelago, punishing slavery as a crime."]