An Aboriginal death in custody inquest has been told a woman who died in a New South Wales police cell was not physically checked or searched for drugs prior to her being detained without arrest.

Rebecca Maher, 36, died in a Maitland police station cell in the Hunter Valley after being picked up in nearby Cessnock in the early hours of July 19, 2016.

Ms Maher was not under arrest but was still detained in police custody overnight.

She was found dead in a cell the next morning and her family was not notified until six hours later.

The custody notification service was one of the key recommendations of the 1991 Royal Commission into Aboriginal Deaths in Custody, and protocols will be examined at this week's inquest.

The inquest in Newcastle will also look at how and why she died, after police were called by witnesses who alleged she was heavily intoxicated.

Her family has campaigned for an inquest into her death — the first black death in police custody in New South Wales in 16 years.

Police launched a critical incident investigation immediately after Ms Maher's death which will also be examined by the coronial inquest, presided over by acting NSW state coroner Teresa O'Sullivan.

Woman detained

Counsel assisting the inquest David Buchanan used his opening address to highlight Ms Maher's final movements before being detained in the cell.

Mr Buchanan said witnesses had seen her wandering the streets of Cessnock, jumping in front of cars and staggering around.

The counsel assisting said officers believed she was on drugs and at that point a senior policeman verbally told colleagues he was detaining Ms Maher as an intoxicated person.

Her family has repeatedly asked why Ms Maher was not taken home — a point raised by Mr Buchanan.

"A sergeant told investigators he didn't attempt to take her to an address she had given as he doubted that she lived at that address," counsel assisting said.

"He also assumed there would be no responsible person there to look after her."

Mr Buchanan then raised the question as to whether Ms Maher should have been detained as an intoxicated person, or whether some other measures should have been taken.

No body search, no physical checks

Rebecca Maher arrived at the Maitland Police Station around 1:30am.

The inquest heard she was unsteady on her feet before sitting on a mattress and continually slumping forward.

"From CCTV footage after 1:29[am] an officer conducted seven visual checks made from the corridor outside the cell and looking through perspex," Mr Buchanan said.

"The evidence is that no police officer entered the cell, no officer had attempted to rouse Rebecca or check on her breathing or her conscious level."

Ms Maher had a history of drug abuse and the inquest was told, despite her dishevelled and drug affected state, she was not searched.

"The police force has a code of practice that states screening people in custody on admission is a most important step in assessing their health and potential for suicide," Mr Buchanan said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 7 minutes 21 seconds 7 m No alcohol or illegal drugs found in system of Indigenous woman who died in police custody: report ( 7.30 )

Ms Maher was found with half a bottle of the potent short-acting benzodiazepine Xanax in her pants at the time she died.

She had been prescribed a bottle with 50 tablets in it the day before.

False belief woman had HIV, hep C

The inquest has been told the officers who dealt with Ms Maher in custody may not have known she was Aboriginal.

"From all the evidence, the court is likely to conclude that someone who was not Aboriginal or who did not know her or family would think she was Caucasian," Mr Buchanan said.

He added that police believed that Ms Maher had HIV and hepatitis C.

"During the journey in the police van, an officer phoned Maitland [Police Station] and spoke to the custody manager and they said they were conveying [an] intoxicated person, in [a] dishevelled state and who was HIV positive," Mr Buchanan said.

The officer also believed that she had a history of self harm and posed a risk.

The counsel assisting said a post mortem examination showed she did not have antibodies for HIV or hep C.

The inquest heard police may have been reluctant to search Ms Maher through fear of contacting either virus, even though the risk of contracting was very low.

Family not told for six hours

The inquest was told Ms Maher was pronounced dead just after 6:00am after unsuccessful attempts to revive her.

The mother of Rebecca Maher, Debbie Small, was not told of her death for six hours despite strict protocols. ( 7.30 )

The initial responding police officer did not know how to use a defibrillator and when paramedics arrived they found she had no shockable rhythm in her heart.

The family did not learn of her death until many hours later, despite strict protocols for notifying relatives stemming from the findings of the 1991 Royal Commission into Black Deaths in Custody.

"Police must notify a next of kin at the first opportunity," counsel assisting said.

"The local area commander is to personally inform or delegate to a fully briefed senior officer, to notify them.

"The family was personally advised at 12:20pm, and that is a matter of concern."

At the time of Ms Maher's death, the Aboriginal Legal Service NSW called for an independent investigation into the death.

The ALS said police failed to alert them to Ms Maher's incarceration as required by changes introduced following the royal commission.

Coroner consoles family

The acting state coroner Teresa O'Sullivan acknowledged the local Aboriginal people which reached out to Ms Maher's family.

"I will start by acknowledging traditional custodians of the land on which we gather, the Awabakal people," she said.

"I pay my respect to all other Aboriginal and Torres Strait Island people and I welcome Rebecca's mother Debbie Small.

"I'm sorry we are gathered here today under such sad circumstances and I am hoping through this hearing many questions can be answered.

"Everyone knows it is a difficult occasion and there will be compassion in this room because you've lost a loved one."

The inquest is set to run for two weeks.