Whatever your opinion on a one-meter passing law, good data is hard to come by to know for sure either way. It might be the #157th most important thing to make riding a bike safer and more popular, or it might be the next best thing after protected bike lanes and filtered permeability. States that have introduced this law have done no before-and-after studies to determine whether there was any effect, beneficial or otherwise. Victoria may introduce a 1m law soon, so time is short to rectify this data deficit and get measurements before a law exists, and to continue with measurement after a law is introduced.
You can help by volunteering to mount a PassBox on your bike for a week on our website for this project at http://passboxmelbourne.com/.