On September 21, 2022, Kimberly Marten gave testimony about Russia’s Wagner Group before the US House of Representatives Oversight Committee’s Subcommittee on National Security. Her themes included what Wagner is and is not, what purposes it serves for Russia, how the US might hold it more accountable for war crimes, and why she does not support labeling it a foreign terrorist organization.
You can read her written testimony here.
You can listen to a recording of the hearing (including her oral testimony) here.