A rebuttable presumption that you may pose a danger to the community or a flight risk may be mandatory but this only means that the focus is back on you for evidence. It is not a shift of the burden of proof, just presentation of your evidence. If you present evidence such as the pretrial services report, self surrender etc., you have made the production and shifted the burden of proof BACK to the prosecutor. The Judge then can weigh all of the other evidence such as the (g) factors. The rebuttable presumption is only a gatekeeper, not a jailer.