Patrick T. Carothers U.S. Marshals Service Hiring Improvement Act of 2017 This bill allows the Director of the U.S. Marshals Service to appoint a qualified candidate to the position of deputy marshal or criminal investigator in accordance with the statutes, rules, or regulations governing excepted service appointments notwithstanding any statutes, rules, or regulations governing appointments in the competitive service. The appointment of a deputy marshal or criminal investigator under this authority shall not be considered to cause the position to be converted from the competitive service to the excepted service. Service by an incumbent as deputy marshal or criminal investigator may not exceed four years. The Director may, upon satisfactory completion of three years of substantially continuous service by a qualified incumbent, convert the appointment of the individual, without competition, to a career or career-conditional appointment.