Janet Jackson’s "accident" in which her breast was briefly exposed in front of 90 million Americans who were watching the Superbowl three years ago returned to a US appeals court on Tuesday.

CBS and the Federal Communications Commission presented oral arguments to a three-judge panel of the Third Circuit Federal Court of Appeals in Philadelphia.

Following the February 2004 incident, the network was fined by the FCC with $550,000 for violating the country's anti-indecency laws.

CBS appealed saying "Lacking any evidence to support the initial speculations about network complicity, the commission instead reached the illogical conclusion that the halftime show was designed to 'pander to, titillate and shock the viewing audience', despite the fact that Viacom did not plan the sole part of the performance the FCC says made it indecent, the 'costume reveal'; did not know about it in advance; did not sanction it (and would not have done so had it known); and took steps to prevent anything at odds with broadcast standards," Reuters reported.

They claimed the incident was unintended and they shouldn’t be punished for something that couldn’t have been foreseen.

CBS Corp. lawyer Robert Corn-Revere said the network took many precautions, including choosing Jackson and Justin Timberlake over more provocative performers, reviewing the script, voicing concerns about ad-libbed remarks and applying a 5-second audio delay.

"I think the precautions CBS took even satisfied the FCC's standards," Corn-Revere said.

However, the FCC disagreed arguing that it was just doing its job in the face of voluminous complaints and that it is on solid legal ground.

Apparently, Justin Timberlake, who performed on the stage by Janet Jackson’s side, did sing the lyrics "Gonna have you naked by the end of this song," and FCC lawyer Eric Miller used the fact as an argument.

The episode, which drew in more than 500,000 complaints from viewers, was described as a "wardrobe malfunctioning." If the fine will be supported, it will be the largest ever levied against a TV broadcaster.

Most recently the commission has had its indecency laws questioned. In June their policies on indecent speech involving the use of the "f-word" by a celebrity at the Billboard Music Awards was rejected by the 2nd US Circuit Court of Appeals.

The court rejected the FCC’s policy on procedural grounds but was "sceptical that the commission can provide a reasoned explanation for its fleeting expletive regime that would pass constitutional muster".