Why would she go to the police if she knew he was innocent?
The police would just show her evidence it was Sheila and charge her of wasting police time.
Now that is being silly Adam,Stan Jones was praying that some evidence would appear to snare Bamber by then.
As it happened she was actually wasting police time.Lizzie and her friends probably spurned her on to go to the police and get revenge on Bamber.Not to see him charged with murder,simply to cause him a bit of hassle by repeating the Matthew story.
And that is indeed what happened,although both got hassle,Bamber and MacDonald.
Now it is worth remembering that at this stage Julie only accused JB of hiring MM to shoot the family.
Indeed she admitted in court that the murders were never mentioned again after 7th Aug when the Matthew story was told to her,and at no time did JB admit to shooting his family himself in the following weeks.
Therefore,after the Matthew story had been proven false ,both JB and MM should have been released without charge and that should have been an end to the matter.
However,by that time the relatives claims had convinced Stan that JB was indeed responsible and he wasn't going to dismiss Julie's evidence,he probably told her that there was other evidence that proved that Bamber was indeed guilty.
Indeed,the police may have convinced Julie that JB was actually guilty and that the plans to kill his family were real and not just spoken in jest.
Then Julie and the police spent almost a year thinking up a credible story to help convict Bamber which mainly consisted of things told to Julie that only the killer could know ,also confessions of being cold hearted and evil,and although these confessions in all likelyhood took place,they wer probably in relation to the break-up,made by JB to comfort Julie and help calm her down.
After all,she was in quite a state over the break-up,even promising JB that she wouldn't do anything silly.
The thing is,by the time Julie went to the police she had nothing to loose as far as Bamber was concerned,it was all over between them.She did however,along with Sue Battersby have a lot to gain by helping the police with agreeing to give evidence against Bamber.Indeed her whole future depended on the police dropping charges against her.