18 U.S.C.S. § 3061(a)(3) expressly empowers the Board of Governors of the Postal Service to authorize Postal Service officers and employees performing duties related to the inspection of postal matters to make arrests without warrant for felonies cognizable under the laws of the United States if they have reasonable grounds to believe that the person to be arrested has committed or is committing such a felony.
A postal inspector received from an informant of known reliability a stolen credit card that respondent had given the informant to be used for their mutual advantage, and the inspector was told by the informant that respondent had agreed to furnish additional cards. At the inspector's suggestion, a meeting was arranged between the informant and respondent for a few days later, which took place at a restaurant. Upon a prearranged signal from the informant that respondent had the additional cards, postal officers made a warrantless arrest of respondent, removed him from the restaurant, and gave him Miranda warnings. When a search of respondent's person revealed no cards, a consented search of his nearby car (after respondent had been cautioned that the results could be used against him) revealed two additional cards in the names of other persons. Following an unsuccessful motion to suppress, these cards were used as evidence in respondent's trial, which resulted in his conviction of possessing stolen mail. On appeal, the Court of Appeals reversed, ruling that the Fourth Amendment prohibited use of that evidence because warrantless arrest of defendant violated his Fourth Amendment rights and that the post-arrest search of defendant's car was coerced.
Did Watson's warrantless arrest violate the Fourth Amendment?
The Court first ruled that defendant's arrest did not violate the Fourth Amendment because (1) it was based upon probable cause, as the government acted upon information from a reliable informant that defendant possessed stolen cards; and (2) the arrest was made pursuant to 18 U.S.C.S. § 3061(a)(3) and 39 C.F.R. § 232.5(a)(3), which authorized the government to make warrantless felony arrests upon reasonable grounds. Therefore, the Court ruled the post-arrest search of defendant's car to which defendant consented to, and which yielded the credit cards upon which his conviction was based, had not been the product of an illegal arrest. That defendant was not informed of his right to refuse consent to the search did not render the search invalid.