[en] The chiral-twin candidate bands recently observed in ¹³⁶Pm have been extended to high spins [I=(21)] using the Gammasphere γ-ray spectrometer and the Microball charged-particle detector array. A more-detailed spectroscopy of the bands was possible, where the rotational alignments and B(M1)/B(E2) ratios confirm that both sequences have the πh_11/2νh_11/2 configuration. Particle-rotor calculations of intraband and interband transition strength ratios of the chiral-twin bands are compared with experimental values for the first time. Good agreement was found between the predicted transition strength ratios and the experimental values, thus supporting the possible chiral nature of the πh_11/2νh_11/2 configuration in ¹³⁶Pm