An Iowa City woman facing charges that she attacked her boyfriend with a knife is now accused of trying to influence his testimony in the case. 19-year-old Bernice Keita was taken into custody Monday night after a reported domestic dispute at her Ellis Avenue residence. Iowa City Police say Keita and her live-in boyfriend had been arguing when she punched him in the face. Keita then allegedly pulled out a utility knife and slashed at him with it, cutting his coat.