318 MARYLAND LAW REVIEW (VOL. 42 Another study, prepared under the auspices of the Joint Commit- tee on Housing created by the State Advisory Board of the Federal Emergency Administration of Public Works, considered the feasibility of the rehabilitation for six particular blighted areas.176 The planners selected these six areas because they were close to better areas, served by an adequate transportation system, and would contribute to the cost of existing streets, schools, sewers, and utilities.177 The study recom- mended restoration and modernization for white habitation of three of the areas, even though all six were primarily populated by blacks.178 In two areas found suitable for black housing, the buildings had decayed "beyond the point of even low level Negro occupancy,179 the sites had "no other value except for Negro residence and never will have,180 and were "certainly only usable for Negro habitation unless commerce and industry can absorb it, which seems doubtful. . . .181 The study was criticized by an Urban League analyst as promoting "newer, bigger and better slums.182 In any case, the removal of blacks from areas where they proved inconvenient or expensive to the white majority had become part of the plan for segregation. Containment was the other strategy. We have already discussed how, when de jure segregation failed, de facto segregation was imple- mented through a conspiracy which restrained residential sales or rent- als to Negroes in white neighborhoods. Once the conspiracy was in place it grew and formalized. Originally it was enforced through peer pressure from neighbors, administrative harassment by housing and health inspectors, and by the suasion of the Baltimore Real Estate Board. Later this conspiracy came to be institutionalized. In 1922 the National Association of Real Estate Brokers (NAREB), of which the Baltimore Board was a member, published a textbook entitled Principles of Real Estate Practice. The textbook em- phasized that "the purchase of property by certain racial types is very likely to diminish the value of other property.183 It was deemed un- ethical to sell blacks property that was located in white neighborhoods. As recently as 1950 the NAREB's code of ethics provided: 176. Report of the Joint Committee on Housing in Baltimore, THE BALTIMORE ENGINEER 6 (Jan. 1934). 177. Id. at 6-7. 178. Id. at 8-10. 179. Id. at 8. 180. Id. 181./« Pub. No. 42, 1973).