Matangi Tonga reports that he changed his plea from not guilty when it was revealed during his evidence that at time police executed a search of his home in March, he had no licence for the .22 rifle.
His counsel had intially submitted the accused had a licence to the firearm.
However, the accused explained he had a licence which expired and he had directed his Parliamentary driver, while he was House Speaker, to renew it.
Tu'ivakano then left for New Zealand and returned later with the belief his licence was renewed.