"Under Constitutional Law" which says that some "little boys" are not protected by the Bill of Rights - i.e. they don't have a 5th Amendment liberty to stay here, since, as the Constitution says, they're not "of the United States". They can be loaded on the railroad car, under the Constitution.
As William F. Buckley said - That non-citizens [on US Soil] have inferior privileges, [one of which is the protection of an unalienable right of liberty] does not offend [one who is not a bleeding heart].