Certainly, precedent helps.  Who sets precedent?  Higher courts.  How do they decide how to rule?  See parent.  Who enforces their precedents against themselves?  Well, no one.<p>A precedent goes against what you wish to conclude?  Distinguish why it doesn&#x27;t apply in these circumstances, depending on how much you fear being overruled.  Keep doing that, until it swallows the rule, if you wish the rule to go away.  In things like evidentiary rulings, you can <i>always</i> distinguish the circumstances, until you go from &quot;a man&#x27;s home is his castle&quot; to &quot;I smelt marijuana &amp; kicked the door down&quot;.<p>In practical &amp; long terms, for issues of government power in particular, predicting how a court will rule is not best done by looking at plausibly applicable precedent.