Chris Hartford is an attorney who's in a same-sex relationship with prison guard Nathan Duarte, despite Hartford already having a wife. When Duarte was suspected of the murder of Carlos Torres, an inmate responsible for outing Duarte in his job, Duarte provided his alibi of meeting with Hartford when his wife wasn't around.
Hartford was personally met when his wife present, but he was taken aside to ask for confirmation. Hartford personally confirmed Duarte was with him around the suspected time Torres was killed. Duarte was definitively cleared when the time Torres was killed was revealed to have been earlier than Duarte's time near Torres. (SVU: "Rotten")