382 A.2d 1035 R. H. Johnson Construction Company and Bituminous Casualty Insurance Company, Petitioners v. Commonwealth of Pennsylvania, Workmen’s Compensation Appeal Board, Gaetano DePiano and Vigilant Insurance Company, Respondents. Commonwealth Court of Pennsylvania.Argued February 27, 1978 May 10, 1978. Workmen’s compensation — Scope of appellate review — Violation of constitutional rights — Error of law […]