I find myself wondering if, this case/similar cases, had been tried in a Scottish Court would the verdict have been 'Not Proven' rather than 'Not Guilty'? I agree that 'Not Guilty' does not always equate to 'Proven Innocent'. It can mean that there was insufficient evidence to prove Guilt conclusively. Many cases in which I had an involvement as a WA worker, boiled down to her word against his word and although you could see that the jury did not believe his version of events ('another man did it and ran away' 'her injuries were the result of self harming' 'she liked a bit of rough sex') they had no 'proof' either way and were forced, under direction from the Sheriff, to put aside personal feelings and only consider facts which could be proved - resulting in either Not Proven or Not Guilty verdicts, with devastating consequences for the 'victim', left at risk of retaliatory harm.
Our Justice System, perhaps adequate to deal with fraud, robberies, carjacking and suchlike is hopeless when it comes to interpersonal crimes, which by their very 'behind closed doors' nature are unlikely to have independent witnesses. No amount of tinkering round the edges of the current system will be able to solve this dilemma. The only solution I can think of is to refer such cases to specialised courts where the case is decided on a balance of probability basis as in civil courts.