This means segregation that comes from personal choice or choices, such as living in certain areas or attending certain places of worship. courts have not become involved in this kind of segregation.

the fourth amendment protects:

"the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."  

so this would mean the denial to search and seizure without warrant or permission.

when the united states took over