Look at the shift in law over time, which should be evidence enough.  For instance, from Bowers v. Hardwick to Lawrence v. Texas, or Roe v Wade to Planned Parenthood v. Casey, in &lt; 20 years.<p>As I said, it is usually the case that precedent is distinguished into oblivion rather than explicitly overruled.  Only very limited technical issues are &quot;settled law&quot;.