Almost half of the appeals undertaken by the Public Defence Service (PDS) in the past 2-1/2 years have been successful, according to the Ministry of Justice.

In the latest issue of its quarterly Justice Matters newsletter, the ministry says over that time the PDS has taken some 55 cases to the Court of Appeal and appeared in two appeals to the Supreme Court.

PDS Director Madeleine Laracy says the success rate compares favourably overall with the success rate in defendant appeals to the Court of Appeal, both in New Zealand and in comparable jurisdictions.

"We don't take on appeals out of an expectation that the appeal will be allowed," she says.

"Our focus is on the defendant's right to appeal and whether the appellant had a fair trial or sentencing."

The newsletter says that "with around 150 lawyers, the PDS is New Zealand's largest law firm".

However, this appears to be at variance with New Zealand Law Society information which shows that at 1 February 2016 there were six New Zealand law firms where there were more than 160 practising certificates held.