NBC News is asking that the campaign of Mitt Romney stop using 1997 footage of a news broadcast for a campaign ad blasting Newt Gingrich.

The Romney campaign ad was unveiled today and essentially lifts then-anchor Tom Brokaw’s report on Gingrich’s ethics violations. The 30-second spot is airing in Florida and is called “History Lesson.”

Brokaw himself issued a statement, via Politico: “I am extremely uncomfortable with the extended use of my personal image in this political ad.  I do no want my role as a journalist compromised for political gain by any campaign.”

Campaigns have from time to time featured news footage in political spots, almost always arguing that it is a fair use of material. But where it skirts the line is when entire passages are lifted from a broadcast. Perhaps the most egregious example during the midterms was when the Senate campaign of Robin Carnahan ran Fox News footage of her opponent in Missouri, Roy Blunt, that showed him in an unfavorable light. Fox News sued, claiming copyright infringement but also arguing that the spots left the impression that the channel was endorsing Carnahan. The suit was eventually settled, with Carnahan’s campaign pulling the spots.

The Romney spot may be pressing the limit even further, as its ads feature nothing other than the Brokaw report and, at the end, the typical disclaimer, “I’m Mitt Romney and I approved this message.” The courts have generally applied a four-factor test to fair use: the purpose and character of the use, the nature of the copyrighted work, the amount of the material taken and the effect of the use on the potential market. What the courts have not decided is just how much footage constitutes fair use and how much is genuine infringement.

Even if the Romney campaign takes down the spot, they have achieved their purpose: Drawing attention to Gingrich’s ethics violations.