75 Pa.C.S. § 2104

Such employees of the Department of Revenue as are designated as special investigators, and who carry identification indicating such capacity, are hereby declared to be peace officers of the Commonwealth, are hereby given police power and authority throughout the Commonwealth to arrest on view without warrant any driver of a qualified motor vehicle engaged in any operations in violation of any provision of this chapter or Chapter 96 (relating to motor carriers road tax) and shall have the power and authority upon probable cause that any such violation may have occurred to search and seize without warrant or process any qualified motor vehicle so operated.