Methods for suturing tissue by forming a locking loop of suture material. In particular, method of using a suture passer to arthroscopically create a locking loop of suture in difficult to access tissues. As used herein a locking loop of suture is a loop of suture that is passed through a tissue from a first side to a second side of the tissue; one or more of the legs of the loop extending from the first side are passed through the tissue to the second side of the tissue and are then passed through the loop, and the loop is cinched to tighten closed over the one or more legs. The resulting locking loops stitches are extremely strong and distribute the stresses across the tissue in a desirable manner.