Police Commissioner Peter Marshall says there were "mistakes in communication'' in the handling of the Roast Busters case, but he does not believe they reflect any supposed "cultural malaise''.
It emerged last week that police had received a complaint from a 13-year-old girl as far back as 2011 about the Roast Busters group, whose members bragged online about having sex with drunk and underage girls.
In his blog on the police website, Mr Marshall said the events of the past fortnight were a "stark reminder'' to police that they must remain absolutely vigilant in matters relating to sexual assault on adults and children.
"I acknowledge there have been mistakes in communication, but I do not believe they reflect any supposed cultural malaise in relation to the 2007 Commission of Inquiry,'' he said, referring to a report by Dame Margaret Bazley which identified a culture of scepticism within police when dealing with sexual assault complaints.
The report urged changes to police attitudes and behaviour.
The Commissioner continued: "There's no indication that we aren't committed to Dame Margaret Bazley's recommendations, despite the assertions of some commentators. Indeed, we're a long way down the path of major culture change.''
The matters came against the backdrop of an increase of 10.8 per cent in sexual offences recorded in the 2012-13 fiscal year. It was encouraging that people were coming forward to make these serious complaints, he said.
"There are scores of prosecutions for such offences before the courts at any one time, and we have approximately 40,000 prosecutions for all offences put before the courts each year. But I repeat we can't afford to fail victims of sexual assault, and if we do the public will not forgive us. Nor should they, given the absolute importance of such investigations.''