Tonga's Solicitor General says the Crown may appeal against the sentences of four men convicted over the sinking of the Princess Ashika.
The former Shipping Corporation of Polynesia's chief executive, John Jonesse, was jailed for five years, the former director of marine, Viliami Tu'ipulotu was given a 3 year suspended sentence.
The ship's first mate, Semisi Pomale, was also given a partly suspended sentence.
And Aminiasi Kefu says the ship's captain, Maka Tuputupu, was sentenced to four years in prison, but it was suspended for 3 and a half years.
"So the bottom line is he has to serve six months. Pomale was sentenced to five years altogether, but he is to serve one and a half years and three and a half years is suspended. We need to sit down and properly consider it, but an initial perception of it, there seems to be some kind of inconsistency in sentence."
Aminiasi Kefu says his office will have to apply to the attorney general if it does decide to appeal the sentences.