In less than one year at least 18 attempted suicides in Western Australia's prisoners were misclassified as acts or threats of self-harm, the state's Inspector of Custodial Services found in a new report out Tuesday.

The review, Recording and Reporting of Self-Harm and Attempted Suicides in Custody, reported in-depth analysis of the 18 incidents between January to September 2023 found for all 18 the person in custody had verbalised an intent to end their life and had acted to fulfil that intent.

The Inspector's review also identified another 20 self-harm incidents which appeared to be attempted suicides, but WA Department of Justice recording did not include whether intent was stated.

WA Inspector of Custodial Services Eamon Ryan said the misclassifications indicated the Department's recording of self-harm and attempted suicide incidents, and subsequent reporting of those incidents to relevant bodies including WA Parliament, could be improved.

The report recommended using a definition of attempted suicide which does not rely on identifying intent, and introducing a clinical review process as two potential mechanisms to ensure incidents are categorised appropriately.

"By accurately recording incidents of self-harm and attempted suicides, the Department can build a better understanding of the extent of the mental health challenges within our prisons and youth detention facilities," Mr Ryan said.

"This information can be used to more accurately provide the resources required on the ground to support the wellbeing of people in custody."

The report also found the Department's reporting system, at the time of the review, did not distinguish between self-harm threats and suicidal behaviours such as thinking, planning, or threatening suicide, and, as a result, the Department had "no visibility" over the extent of suicidal behaviours being exhibited by people in custody.

Mr Ryan acknowledged the Department's recent introduction of a "suicide threat" category, which he expects will improve the recording accuracy of these incidents.

Kurin Minang human rights expert and law academic Dr Hannah McGlade told National Indigenous Times that the Inspector's Office had "revealed a systemic issue in WA prisons showing the lack of proper identification of suicide risk and attempts".

"This is completely unacceptable; Aboriginal lives at on the line here and there have already been a number of deaths in custody in WA in the past 12 months," she said.

"The serious issue of Aboriginal deaths in custody remains ongoing in Australia more than three decades after the landmark Royal Commission brought down hundreds of recommendations, many of which remain unimplemented."

Dr McGlade, who is also a member of the UN Permanent Forum on Indigenous Issues, said that more broadly, "we are not seeing the political will to address the situation of over-incarceration and the failure to implement the Royal Commission recommendations, in particular the use of incarceration as a last resort".

"Draconian laws, in particular the High Risk Serious Offenders Act 2020, must be repealed. It's a clear violation of human rights and is discriminatory against at risk Aboriginal prisoners," she said.

"We have too many Aboriginal prisoners on remand - who have not been convicted of an offence - and it is known they are at increased risk of suicide. We need bail reform urgently, and measures including bail hostels and appropriate accommodation in place."

WA-based National Suicide Prevention and Trauma Recovery Project director Megan Krakouer told National Indigenous Times she has "no confidence in the Department" with the recording of self harm incidents.

"At the coronial evidence for Cleveland Dodd guards gave evidence that they could not record each cry for help due to staffing issues," she said.

"There will be no accountability regarding accuracy as it is an internal process. Vital information needs to be made available publicly, or at the very least provided - on a mandatory basis - to the WA Children's Commissioner (WA).

"Our people are dying at rates never seen before, cruelty inflicted, and a system which does not rehabilitate young offenders. The government of WA should hang its head in shame and stop coming up with mediocre measures."

WA Department of Justice director general Kylie Maj said the Department was committed to prisoner safety and wellbeing and took every measure possible to reduce and prevent occurrences of self-harm and attempted suicide in prisons.

"Accurate recording and reporting of such incidents is crucial to data analysis to identify risk, develop and implement targeted prevention strategies and facilitate supports for at-risk prisoners," she said.

"It also enables the Department to fulfil its reporting obligations to national data collection agencies, with a particular focus on the prevention of Aboriginal deaths in custody."

The Department said it has updated policies and procedures in recent years, including adding a new 'suicide – threat' category to the incident reporting system.

Commissioner for Corrective Services Brad Royce said the new occurrence type differentiates self-harm threats from suicide threats, recognising not all self-harm incidents involve suicidal intentions.

The OICS report was focussed on reporting and recording systems, and did not assess individual cases or the causes of self-harm or attempted suicide in custody, or the quality of care provided to people in custody who had engaged in an act of self-harm or who had attempted suicide.