The HOA's had rules that black and other undesirables weren't allowed. Enforceable since HOA's were a private associations. However the supreme court also rule

The HOA's had rules that black and other undesirables weren't allowed. Enforceable since HOA's were a private associations. However the supreme court also ruled that was unenforceable too. But that didn't happen before developers realized that they could use HOA's as a cash cow. You sell a house once. But you can collect HOA dues for a couple of decades after. There is a case in Daily City where it took decades for home owners to get rid of the HOA. That collected dues and provided absolutely nothing in return.