Carol McEwan is one of the mistresses of unfaithful cop Michael Provo. Per Provo's modus operandi, he found McEwan because her husband Eddie Baker was supposed to do serious time for drug possession but was released for good behavior, and since Baker was abusive to Carol, Provo threatened to tell him about the affair if she ever tried to leave or ruin the relationship, hypocritically disregarding Provo's own wife.
When Provo brutally raped Jesse Sturgis, another mistress, before shooting her abusive boyfriend Tommy Bandolce and framing her for the crime, McEwan was tracked and questioned. After some reluctance, she admitted she was afraid Eddie's unstable nature would finally peak in a murderous rage if she told. Despite her disgust over the detectives also ready to tell Eddie about the affair, she testified to Provo's infidelity to save Jesse.
She also revealed she was threatened by Provo into making a 911 call that framed Jesse for the murder, which was also coupled with the threat of sending Eddie to jail since Provo covered his records. Because of the deal, she was never charged after her testimony. (SVU: "Beautiful Frame")