Paedophile dance teacher Grant Davies could not be arrested when complaints were first made against him in 2007, police say, telling an inquiry they did not have enough evidence.

NSW Police detectives from the Joint Investigative Response Team (JIRT) – a multi-agency child abuse taskforce – have defended the two months it took to enact a search warrant on Davies’ home after receiving complaints from two young students in 2007.

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Detective Sergeant Kirsty Hales also revealed the unit had just five and sometimes even fewer investigators working on 36 cases at the time it was handling the aborted Davies investigation.

Davies, co-founder of the RG Dance school in inner Sydney, continued abusing students until he was finally arrested in 2013.

On Friday Detective Sergeant Hales said police had statements from two female students at RG Dance in March 2007 detailing Davies’ sexual offences.

One student, codenamed BZP, was 15 by 2007 but had been abused by Davies since the age of nine.

In her statement, BZP detailed MSN Messenger messages from Davies encouraging her to masturbate and describing a sexual dream he had had.

Detective Sergeant Hales said the signed statements of BZP and another student, BZM, were not sufficient evidence on which to obtain a search warrant for Davies’ computer and arrest him in March, 2007.

“We would like to put every matter before the court. That doesn’t mean we are going to get a conviction,” Detective Hales said.

“We run the risk of getting an acquittal.”

JIRT officers were put on the Davies investigation in March, 2007, the commission heard.

However, police did not execute a search warrant on Davies’ home until May 14 that year, by which time he had got rid of his old computer, had retained a lawyer and refused to talk with police.

Computers were seized during the raid but electronics specialists found no evidence.

The investigation into Davies was discontinued in 2008.

JIRT member Detective Senior Constable Jason Madsen said he believed BZP’s allegations but not enough supporting evidence could be found.

Detective Senior Constable Madsen said conducting the search warrant was delayed by JIRT’s heavy case workload and by the time it took to coordinate search warrant raids with other agencies, including the State Electronic Evidence Branch.

He agreed with counsel assisting the commission David Lloyd that the delay was unacceptable but said such delays could happen because of detectives’ workload, with new and urgent cases referred to JIRT all the time.

Detective Senior Constable Madsen also said police did not try to contact parents of other children attending RG Dance, which had 250 students, to assess the risks posed by Davies.

“You can’t go fishing for other victims, you’ve got to look after the care and welfare of the children,” he said.

Davies was arrested in April 2013, after his wife found offensive messages and photographs of children on his computer and went to the police.

In 2015 Davies pleaded guilty to 47 counts of sex offences against nine students.