Public Housing in NYC can be all over the place as far as what kind of folks are living there. In Manhattan’s East Village and Lower East Side all along the East River are projects. I would say the majority of folks living in them now are senior citizens who have lived there for many years...mostly Hispanic. These folks I doubt are doing bong hits.
What I was getting at is that there is precedent for this requirement and it may be legally/constitutionally sound. I realize that public housing shelters folks from one end of the spectrum to the other. If they are not taking drugs, they wouldn't have much to lose now, would they?
It would be my guess that there is no drug testing for public housing in my state, as a drive my the projects reveals a bunch of people who all look like they are drunk, high or stoned, or a combination thereof.