The head of Garda Analysis says he raised concerns about a report into homicide figures because of the way crimes were classified.

It comes after gardaí reviewed 524 deaths and reclassified 12 as homicides.

The Policing Authority is to conduct an independent review, despite the gardaí saying the cases were properly investigated.

Earlier, the Oireachtas Justice Committee questioned senior members of the force about the misclassification.

Gurchand Singh, Head of Analysis, says he previously said that they needed to rely on case files when classifying crimes, as well as Pulse and State Pathologist reports.

Dr Singh says he also felt that the classification of some crimes contradicted their own rules.

He observed: "For example, there was an injured party that was deceased. The offence was down as an assault causing harm.

"Our own crime-counting rules say that [when] an assault causing harm and subsequently someone has died because of that assault, that should be upgraded to a homicide. We had examples of those on the systems."

He added: "There were times when I couldn't reconcile what was there."

On the subject of an internal review of figures, he observed that he 'didn't agree' with some of the classifications.

He told deputies that he raised his concerns with Garda management, although noted that his team did not get to sign off on the final report.

The review into the misclassification of homicide figures is expected to take at least six months.