Charges against a NSW police officer accused of fatally tasering a 95-year-old grandmother will be upgraded to manslaughter.

Clare Nowland, who had dementia, died after she was allegedly stunned by Senior Constable Kristian White, 33, in her Cooma aged care home in the early hours of May 17.

She was confronted by police as she used a walking frame and holding a steak knife before she was tasered and fell, hitting her head on the ground.

Ms Nowland spent a week in hospital after sustaining critical injuries, including a fractured skull, before she died.

White was charged with recklessly causing grievous bodily harm, assault occasioning actual bodily harm and common assault.

An additional charge of manslaughter has been laid against the senior constable following advice from the Office of the Director of Public Prosecutions, NSW Police said in a statement on Wednesday. 

The force has fielded criticism for not revealing for 36 hours that a Taser had been deployed during the incident, previously claiming the delay was needed to inform Ms Nowland’s family.

However, the claim was undermined by an internal police document released last week showing the senior next-of-kin was informed by midday on May 17.

AAP previously revealed police removed any mention of paramedics, a knife and a Taser in their first statement issued on the afternoon of May 17.

White remains suspended from duty with pay and will next appear in court on December 6.

Ms Nowland’s family is suing the state of NSW and appealing to view bodycam footage of the incident.