AT&T and T-Mobile's advertising dispute has now involved a legal challenge with an advertising watchdog.

AT&T is suing the National Advertising Division to defend its advertising campaign, which criticizes T-Mobile. The corporation is suing the advertising watchdog rather than its competitor.

AT&T launched an ad campaign, called "Ain't Our First Rodeo," that directly targets T-Mobile. The commercials state that the NAD, an advertising review division of the Better Business Bureau, has found T-Mobile's advertising to be false or misleading at least 16 times over the past four years. The NAD asked AT&T to discontinue the campaign because it violates the agreement that NAD findings cannot be used for self-promotion.

AT&T chose to file a lawsuit against the NAD. The company is seeking a court declaration affirming its First Amendment right to "speak truthfully" about T-Mobile's history. AT&T publicized the lawsuit via a blog post with a link to the complaint, declaring that it is a consumer advocate.

This legal action involves the industry's self-regulatory organization. T-Mobile has worked to establish its "Un-carrier" brand by offering transparent billing and "price lock" guarantees. AT&T is challenging that image, citing the NAD's previous conclusions.

AT&T's complaint alleges that T-Mobile exploits the NAD process, allowing them to run "deceptive advertisements" for extended periods. AT&T is accusing T-Mobile of being untruthful and the NAD of being unable to stop them, leaving consumers unsure of whom to believe.

Both T-Mobile and AT&T have been known to make dubious claims. The entire industry struggles with transparency.

The NAD does not want its decisions used in a competitor's advertising campaign, which is standard practice. AT&T appears to be attempting to portray itself as the "truthful carrier," but its reputation is not unblemished. Suing the watchdog is a bold strategy. The court's decision is unknown, but the case will be interesting.

AT&T's advertising campaign against T-Mobile has had unexpected consequences. AT&T is publicly accusing T-Mobile of dishonesty.