Helen Katisch is a call girl whose testimony was solicited by Regina Mulroney and Gus Iacone to illegally exonerate Regina's daughter Stephanie for murder.
When Iacone had associate Cesar Ordoniez murder Stanley Becker, Katisch was hired as a "witness" to frame serial killer Arthur Pruitt. When Pruitt was arrested, she flatly and sarcastically identified him as agreed to in the lie. (SVU: "Entitled")
When Stephanie's guilt was revealed and the evidence was reviewed, Katisch was interrogated again. She confessed and was arrested, taking a plea to testify against the Mulroneys, which didn't succeed in a conviction. (L&O: "Entitled")