Melanie Carver is a U.S. Senator running for reelection. Her reelection campaign was assisted by bundler Victor Vargas, who was found out by affiliate Sean Witt to actually be a career con artist and embezzler. This resulted in Vargas killing Sean and his two roommates.
Vargas brought the very candidates he campaigned for to the stand for questioning, insinuating each of them had motives for murder, including Melanie, all because they affiliated with Vargas. Melanie was encouraged by McCoy, a personal friend of hers, to get Vargas recorded to say on record in their confrontation in the bathroom that he was manipulating everyone. This was used to make him admit on the stand all his crimes were for adoration, pleading for Melanie to affirm she liked him.
After Vargas was found guilty, McCoy asked why Vargas said there was more on the tape, but Melanie just said she had to get ready for the upcoming election. (L&O: "Political Animal")