Monday Pop Quiz: Rehnquist Edition

The late Justice William H. Rehnquist joined Justice White in the dissenting opinion in the landmark case, Roe v. Wade. Rehnquist argued on two points that the finding was flawed, one of them being that the construction of privacy relied on by the ruling was completely erroneous:

A transaction resulting in an operation such as this is not "private" in the ordinary usage of that word. Nor is the "privacy" that the Court finds here even a distant relative of the freedom from searches and seizures protected by the Fourth Amendment to the Constitution, which the Court has referred to as embodying a right to privacy.

What was the other key flaw in the ruling that Rehnquist cites?

Cross-posted at Guide to Midwestern Culture.