The partial photoionisation cross section and the photoelectron angular distribution parameter have been determined for each spin-orbit component of Ar ²P in the region of the autoionisation resonance 3s to np(n=4, 5, 6). The variation of the properties was found to be similar for both components; however, there may exist an indication of small effects from spin-orbit coupling and electron correlation. Agreement between RPA results and the data for the n=4 resonance is satisfactory.