For you non-lawyers out there, yes this sometimes happens. Lawyers really do learn useful things in law school and know things mere mortals don’t! (But not everything, so it doesn’t hurt to do your homework.)
From the OSB Litigation Section Newsletter (and they put it online – thank you!), July 2008 issue, this article by Caroline Harris Crowne & Julia E. Markley: “Federal Arbitration Act Preempts Oregon’s Legislature’s 2007 Amendement to Oregon Arbitration Act.”
“… In 2007, the Oregon legislature imposed a restriction on certain kinds of arbitration agreements that flies in the face of U.S. Supreme Court case law. ORS 36.620(5), part of Oregon’s version of the Revised Uniform Arbitration Act (“OUAA”), now requires that, in order for an arbitration agreement between an employer and employee to be valid, either the employer must give the employee two weeks’ notice before the first day of employment that an arbitration agreement is required as a condition of employment or the arbitration agreement must be entered into upon a “subsequent bona fide advancement” of the employee….” (full article from here, p. 4)
So, if you want to read about things like, supremacy of federal law, the Commerce Clause, and preemption doctrines, go to law school! No, not really (unless you really want to). But you can learn a lot about these concepts in, uh, books about the law, and maybe even on the web.