Did the D.C. Circuit err in deferring to FERC's interpretation of its own precedent?

QUESTION PRESENTED With the aid of a unique form of judicial deference, Phillips Pipeline LLC (“Phillips Pipeline”) has transformed what should be a common-carriage pipeline into a monopoly that serves only its affiliate, Phillips 66 Company (“P66”). Previously, the Federal Energy Regulatory Commission (“FERC”) had considered and rejected similar ploys to sidestep the statutory requirement that common carriers provide transportation to all customers upon reasonable request. Here, however, the Commission ignored those precedents and pivoted to a narrow reading of its jurisdiction that excludes even market-cornering behavior by an affiliated corporation. The D.C. Circuit affirmed this approach by “defer[ring] ... to the Commission’s interpretation of its own precedent.” App. 6. This novel form of deference, embraced in the Sixth and D.C. Circuits, first arose in Cassell v. FCC, 154 F.3d 478 (D.C. Cir. 1998), decided the year after this Court decided Auer v. Robbins, 519 U.S. 452 (1997). The question presented is: Did the D.C. Circuit err in deferring to FERC’s “interpretation of its own precedent” in the absence of a reasoned explanation for departing from the standards embodied in those precedents?