Jeff Krause is a defense lawyer in Baltimore, Maryland he was assigned to help defend Dean and Sam with their charges.
Background
He first appears in Dean's holding room and attempts to help Dean by giving him legal advice. Dean doesn't pay any attention however, and instead asks him for a pen and begins writing. Once done, Dean asks Jeff if he recognizes anything from the words Dean wrote down. Jeff is confused, but does it anyways. Jeff informs him that the words spell out a street name, "Ashland". Dean asks Jeff to bring a message to Sam. So Jeff goes into Sam's holding room, and gives him the message. Jeff attempts to help Sam but is interrupted when he is informed by Diana that Dean is "confessing". Jeff rushes over to stop Dean, but the "confession" wasn't what he expected.