PUC from litigating the Eleventh Amendment issue now. Collateral estoppel prevents the relitigation of issues that have been decided in a previous action. See Hawksbill Sea Turtle v. Federal Emergency Management Agency, 126 F.3d 461, 474 (3rd Cir.1997). It “protect[s] litigants from the burden of relit-igating an identical issue with the same party or his privy and ... promotes] judicial economy by preventing needless litigation.” See id. (citing Parklane Hosiery Co. v. Shore, 439 U.S. 322, 326, 99 S.Ct. 645, 58 L.Ed.2d 552 (1979)). The issue of the PUC’s Eleventh Amendment immunity has already been thoroughly litigated between Amtrak and the PUC in this Court. See National Railroad Passenger Corp. v. Com. of Pennsylvania Public Utility Com’n, 1997 WL 597963, at *6-10 (Sep. 15, 1997) (<HOLDING>); National Railroad Passenger Corp. v. Com. of
holding that a county is not an arm of the state for purposes of the eleventh amendment holding that the fsba was an arm of the state for diversity purposes holding that the university of colorado is an arm of the state for purposes of sovereign immunity holding that the anne arundel board of education is an arm of the state for purposes of eleventh amendment immunity holding that the puc is not an arm of the state and rejecting claim of immunity