When reading Brett Christian's articles in the Post he does seem to present a biased attitude against the police. For example in the article in your post he presents the CG evidence as though it were missed. However, it is just as likely that advances in forensics have enabled DNA to be recovered that was not known to exist in the late 1990s. They can get DNA from a fingerprint now, in the 1990s that would have been impossible.
I'd like to present an opposing view, if I may. Bret Christian is the unsung hero of this case: He would not let it go. He would not allow the Police, in their bumbling ineptitude, to just let the case drop, as they had in a number of cases such as Julie Cutler (I'll get to Julie in a mo'). He was the one who convinced his various media overlords to fund trips to the US to speak to forensic experts and he was the one who tried to impartially present a contrary view when the police insisted they'd "got their man", not once but twice!
In the journo community, it's reasonably well supported that Christian was the dog with the Police bone who "kept the bastards (coppers) honest", to misquote Don Chipp. *mods, this is a well used part of the Australian vernacular - not suggesting that coppers are inherently or explicitly "bastards".
He was relentless. Better, he was relentless and objective and helpful. He was the one who interviewed the FBI profiler, he raised the funds to see that guy, hoping, yes, for a scoop, but, also, to assist the then floundering police with the investigation.
It has to be said that if Christian hadn't kept the police nose to the investigation grindstone, and offered alternative ways to look at the case and then writing about it to keep the pressure up, this outcome may not have happened.
In the case of Julie, dear lovely Julie, the police were initially hopeless. It was the parents of the community who put pressure on the Police to treat her disappearance as serious. The Police were very reluctant. It was the mums really, who had somewhat mothered Julie and her sister after the death of their own mum, who insisted that Julie's disappearance was sinister. It was the dads (not her own; he lived in Kal) who went to Peppermint Grove police and insisted that Julie's disappearance was worrying. The next day her car turned up at the end of Cott groyne. The Police were still reluctant to act.