There's a legal precedent that I can't recall saying this is unconstitutional

How the hell is this even constitutional? From the article:

Mayor Norman McCourt said starting Wednesday the city will begin trying to evict groups who do not fit into Black Jack’s definition of family ...

The current ordinance prohibits more than three people from living together unless they are related by "blood, marriage or adoption." The defeated measure would have changed the definition of a family to include unmarried couples with two or more children.

EDIT (05/18/2006): Oops, in my zeal to properly format the post, I must have accidentally erased the hyperlink. In any case, here's the article. Sorry for the confusion!