The Courts and Criminal Matters Act came into force yesterday, allowing application to the High Court to force asset sales to recoup court-imposed reparations and fines.

Anthony Saxton, and son, Morgan Saxton, who has since died, were convicted in 2007 of stealing snowflake pounamu from the Cascade Plateau in South Westland.

The pair were ordered at a 2008 sentencing to pay $300,000 reparations.

Ministry of Justice general manager collections Bryre Patchell said Anthony Saxton had not paid any of the $300,000 owed.

"Court staff have considered seizing property and making compulsory deductions from Saxton's income," he said.

"However, these options were not appropriate so a charging order was placed over his Haast property, meaning it cannot be sold unless the full amount of reparation is paid.

"Provisions under the Courts and Criminal Matters Bill will allow court staff to apply to a High Court judge for a sale to force the sale of the property."

Police seized some of the pounamu from the Haast property and returned it to Ngai Tahu. But some was unaccounted for.

Anthony Saxton's life has been marred by tragedy since his sentencing. Morgan Saxton died when his helicopter crashed into Lake Wanaka in November 2008.

Saxton's other son, Darren Saxton, 25, died in a car crash near Haast last June.

Saxton had been sentenced to two years and nine months in prison, but the Court of Appeal substituted this with home detention.

Courts Minister Chester Borrows said the new law would target offenders with no intention of paying court-imposed fines.