Popular constitutional law expert and media commentator George Williams has thrown his wig in the ring for one of two soon-to-be-vacant positions on the High Court, telling Crikey he's "very interested" in a prized position among Australia's top judges.

The dual appointments to replace the imminently retiring William Gummow and Dyson Heydon -- and apparently known in beak circles as Roxon's Gift -- are set to be announced later in the year by the Attorney-General when her recommendation is ticked off by Federal Cabinet.