DirecTV fired off a letter to the FCC accusing News Corp.-owned Fox Networks of employing misleading advertising in their carriage dispute.

In a letter to FCC chief William Lake issued Thursday, Derek Chang, DirecTV’s exec VP of content strategy and development, also knocked Fox for bad-faith negotiations. “Fox is clearly abusing the public trust by its deliberate attempt to confuse and alarm consumers,” Chang wrote. “Such conduct is certainly not what the commission had in mind when it made Fox a steward of the nation’s airwaves entrusted to serve the public interest.”

The prospect of FCC intervention was raised last year in the last major carriage dispute between News Corp. and Cablevision, which was marked by a two-week blackout of the Fox network.

The crux of DirecTV’s complaint is the following phrase that Fox has used in ads alerting consumers to the controversy: “Soon, in some markets, you may lose your local Fox station.”

As Chang notes in the letter, DirecTV has only suggested it will cease transmitting Fox’s cable channels as of Nov. 1 — not the broadcast signal on Fox owned-and-operated stations, which is subject to a separate agreement that doesn’t expire until the end of the year.

The carriage dispute first went public last Friday.

DirecTV also notes that Fox has run TV ads that show clips from broadcast programming like “Glee” that isn’t on the 20-odd cable channels that could get yanked by Nov. 1, including FX, Fox Movie Network and National Geographic Channel.

In addition, Chang charges that Fox hasn’t made a “separate” offer to keep the broadcast property on the air. As Variety first reported, News Corp. has sought to combine both the broadcast and cable agreements into one dispute — and may want to also include other cable channels covered under separate agreements, including Fox News Channel.

A letter to the FCC has become an increasingly frequently used tactic for escalating a carriage dispute.

Last year, the Cablevision-Fox conflict escalated to the point that Sen. John Kerry floated a bill recommending that programmers and distributors would have to negotiate in a FCC-mediated process that could end in binding arbitration. FCC chairman Julius Genachowski urged both sides to reach an agreement at the time, but the dispute was resolved before any further action was taken.