P believed that the FCC has unreasonably delayed determining whether American Telephone and Telegraph Company ('AT&T') must reimburse ratepayers for two separate instances of allegedly unlawful overcharges. P had petitioned the FCC to investigate and to require AT&T to reimburse customers. The FCC issued a Notice of Inquiry seeking public comment and for the next five years sat and did nothing. Congressional prodding produced two promises to act but nothing happened. P finally petitioned the court for mandamus.