A teenager named Rosa Wolf was reported dead at the entrance of town with her throat slashed. After gaining enough evidence, the Grimsborough PD' intel suggested that Matt Barry and Ash Bison were suspected of murder, in which Matt was found guilty of grand homicide.
Since this case strictly works as a "tutorial case", Matt's motive for killing Rosa was not stated as he was given an automatic lifetime jail sentence without Judge Hall's intervention. The player was then permitted to move on to the next case (although they can elect to interrogate Ash Bison later) as gratitude for completing the case.