The NSW director of public prosecutions has apologised to Lynette Daley's family for delays in the case after two men were jailed over her sexual assault and death.
Ms Daley, 33, died after a violent sex act with her boyfriend Adrian Attwater and his friend, Paul Maris, on a drunken 2011 Australia Day camping trip to Ten Mile Beach near Iluka.
Although the pair was initially charged over her death, the DPP in 2012 decided not to proceed with their prosecution and in 2015 declined to recommence proceedings.
When they eventually went to trial in 2017, it took a jury just 32 minutes to find Attwater guilty of manslaughter and aggravated sexual assault and Maris guilty of aggravated sexual assault and hindering the discovery of evidence.
"Some of the evidence that informed the earlier decisions not to proceed with the prosecution was different to the evidence that was before the jury," NSW Director of Public Prosecutions Lloyd Babb SC said in a statement on Friday.
"Nonetheless, I sincerely regret my office's involvement in the delay."
In the NSW Supreme Court in Coffs Harbour on Friday, Attwater was jailed for at least 14 years and three months while Maris was sentenced to at least six years and nine months behind bars.