Complex segments consisting of two phases are potentially ambivalent as to which phase determines their phonemic status - e.g. whether /tn/ is a stop or a nasal. This theoretical problem is addressed here with respect to a typologically unusual phoneme in Hiw, an endangered Oceanic language of Vanuatu. This complex segment, /gL/, combines a velar voiced stop and a velar lateral approximant. Similar phonemes, in the few languages which have them, have been variously described as (laterally released) stops, affricates or (prestopped) laterals. The nature of Hiw /gL/ can be established from its patterning in tautosyllabic consonant clusters. The licensing of word-initial CC clusters in Hiw complies with the Sonority Sequencing Principle, albeit with some adjustments. Consequently, the well-formedness of words like /megLejininverted e/ 'berserk' relies on /gL/ being analysed as a prestopped velar lateral approximant - the only liquid in the system.