* Marital status is a protected class. You can't consider it when hiring. * Age is a protected class. You can't consider it when hiring. * Pregnancy is a proxy for sex, a protected class. You can't consider it when hiring [1]. * Parental status is a protected class, but apparently is not applicable to Employment cases [2]. So you could get away with avoiding parents in some places. But man, what a great way to violate the No Asshole rule. Frankly, I'd rather not work for a startup that would want to go down this path.

[1] http://users.aristotle.net/~hantley/hiedlegl/statutes/title7... [2] http://www.seattle.gov/civilrights/discrimination.htm