(concurring).
I am happy to go along with the court’s opinion, but I believe there is a shorter approach. The close decision in Loper seems clearly to have turned on the lack of integrity, or reliability, of the prior fact finding process. Since the Court has given retroactive effect to Gideon v. Wainwright, 1963, 372 U.S. 335, 83 S.Ct. 792, 9 L.Ed.2d 799; Doughty v. Maxwell, 1964, 376 U.S. 202, 84 S.Ct. 702, 11 L.Ed.2d 650, reversing Doughty v. Sacks, 1963, 175 Ohio St. 46, 191 N.E.2d 727; see Pickelsimer v. Wainwright, 1963, 375 U.S. 2, 3-4, 84 S.Ct. 80, 11 L.Ed.2d 41 (Harlan, J., dissenting), the Loper holding is a logical extension of that case. The Court, however, has not given retroactive effect to Mapp v. Ohio, 1961, 367 U.S. 643, 81 S.Ct. 1684, 6 L.Ed.2d 1081; see Linkletter v. Walker, 1965, 381 U.S. 618, 85 S.Ct. 1731, 14 L.Ed.2d 601; Desist v. United States, 1969, 394 U.S. 244, 89 S.Ct. 1030, 22 L.Ed.2d 248, and the reasons given by the Court for distinguishing Gideon from Mapp convince me that, with due respect to Beto v. Stacks, 5 Cir., 1969, 408 F.2d 313, the nature of the constitutional defect does make a difference in this kind of case. Basically the Mapp rule was of constitutional proportions because of its prophylactic importance, *97rather than because of its prejudicial effect on the defendant’s trial. See 367 U.S. at 652, and at 656, 81 S.Ct. 1684, quoting from Elkins v. United States, 364 U.S. 206 at 217, 80 S.Ct. 1437, 4 L.Ed.2d 1669. Even though in the case at bar the vulnerable prior conviction was post Mapp, I cannot believe the Court would apply the Loper rule in a Fourth Amendment case. Indeed, we may be said to have foreshadowed this distinction in Gilday v. Scafati, 1 Cir., 1970, 428 F.2d 1027.