Police investigating the alleged kidnapping and murder of a Ngāruawāhia man whose body was found dumped at McLaren Falls have arrested a woman on methamphetamine charges.

The 26-year-old from Hamilton appeared in the Hamilton District Court on Tuesday afternoon.

She is facing charges of supplying methamphetamine and possession of methamphetamine for the purposes of sale.

The alleged offending period is from July 9 to July 27 this year, and the offences are alleged to have taken place in Hamilton.

Through her counsel Rob Weir she pleaded not guilty to the charges and was remanded on bail to next appear on September 13.

Weir also applied for name suppression for his client, however this was declined by Judge Robert Spear. Weir immediately gave notice he would be appealing the suppression decision, and the woman was granted interim suppression for an appeal to be lodged. This must be done by midday on Thursday, or the suppression will lapse.

The charges come as a result of investigations into the death of Mitchell Paterson, a 26-year-old father of one, who was found dead in the water beneath the McLaren Falls bridge in the lower Kaimai Ranges, near Tauranga, on July 13.

He died of injuries inflicted in an assault.

Dinsdale man Simon Peter Walker, 36, has been charged with murdering Paterson, as well as one charge of kidnapping him.

Christopher Ramia Smith, 34, Grant Stewart Wickens, 33, and Leon Colin Wilson, 49, are each charged with manslaughter in relation to Paterson's death.

James Lee Green, 27, is charged with being an accessory after the fact to murder and driving while disqualified.

Those defendants have been allocated a trial date of July 1 next year, and will next appear for a case review hearing on October 16.

- Stuff/Mike Mather.