Editing Precedent (section)

=== Hierarchy of courts ===

==== Federalism and parallel state and federal courts ====
In federal systems the division between federal and state law may result in complex interactions. In the United States, state courts are not considered inferior to federal courts but rather constitute a parallel court system.
*  When a federal court rules on an issue of state law, the federal court must follow the precedent of the state courts, under the [[Erie doctrine]]. If an issue of state law arises during a case in federal court, and there is no decision on point from the highest court of the state, the federal court must either attempt to predict how the state courts would resolve the issue by looking at decisions from state appellate courts, or, if allowed by the constitution of the relevant state, [[certified question|submit]] the question to the state's courts.<ref>{{cite web |title=Mandatory v. Persuasive |url=http://faculty.law.lsu.edu/toddbruno/mandatory_v__persuasive.htm |url-status=dead |archive-url=https://web.archive.org/web/20121025142246/http://faculty.law.lsu.edu/toddbruno/mandatory_v__persuasive.htm |archive-date=25 October 2012 |access-date=2 November 2012 |publisher=Faculty.law.lsu.edu}}</ref>
* On the other hand, when a state court rules on an issue of federal law, the state court is bound only by rulings of the Supreme Court, but not by decisions of federal district or circuit courts of appeals.<ref name="40 Cal. 4th 1370, 1416">''People v. Leonard'', [http://online.ceb.com/calcases/C4/40C4t1370.htm 40 Cal. 4th 1370, 1416] (2007) (Ninth Circuit decisions do not bind Supreme Court of California).</ref><ref>{{cite journal |last1=Martin |first1=John H. |date=1972–1973 |title=51 Texas Law Review 1972-1973 Binding Effect of Federal Declaratory Judgments on State Courts Comment |url=http://heinonline.org/HOL/LandingPage?collection=journals&handle=hein.journals/tlr51&div=41&id=&page= |journal=Texas Law Review |volume=51 |page=743 |access-date=2 November 2012}}</ref><ref>[[United States federal courts]]</ref> However, some states have adopted a practice of considering themselves bound by rulings of the court of appeals embracing their states, as a matter of comity rather than constitutional obligation.<ref>{{cite web |last=Wrabley |first=Colin E. |year=2006 |title=Applying Federal Court of Appeals' Precedent: Contrasting Approaches to Applying Court of Appeals' Federal Law Holdings and Erie State Law Predictions, 3 Seton Hall Circuit Rev. 1 |url=http://m.reedsmith.com/files/Publication/f2d6419f-4ea8-4b31-a1f2-e2c5752ac77d/Presentation/PublicationAttachment/84ab3eeb-9a19-419c-9776-009a4e40288a/Wrabley.pdf |url-status=dead |archive-url=https://web.archive.org/web/20161017100213/https://m.reedsmith.com/files/Publication/f2d6419f-4ea8-4b31-a1f2-e2c5752ac77d/Presentation/PublicationAttachment/84ab3eeb-9a19-419c-9776-009a4e40288a/Wrabley.pdf |archive-date=17 October 2016 |access-date=2 March 2016 |website=m.reedsmith.com}}</ref>

In practice, however, judges in one system will almost always choose to follow relevant case law in the other system to prevent divergent results and to minimize [[forum shopping]].