http://www.postal-reporter.com/blog/postal-police-sue-usps-dejoy-over-restrictions-they-claim-put-postal-workers-in-danger/
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On August 25, Postal Police workers were informed of a new directive by Deputy Chief Inspector David Bowers that said officers no longer had any law-enforcement authority, whatsoever, except when they are physically stationed on real estate owned or leased by the Postal Service, reversing officers previous ability to protect U.S. mail and postal workers off of USPS premises.
Postal Police officers previously would go off-site to protect letter carriers and the mail in dangerous areas, to stop mail theft from carriers and from collection boxes, and to insure the safety of the mail at airports, the lawsuit explains, noting officers responded to an increase in attacks on mail carriers and crimes like mail fishing to steal mail from USPS collection boxes.
While Postal Inspectors have similar law-enforcement duties to Postal Police officers, they typically work only during business hours, the lawsuit notes, making Postal Police officers, who work around the clock, the only ones capable of handling issues that happen outside of regular business hours.