There have been the same breaches/misuses/crimes in the Victorian Police and doubtless every other agency with access to similar information. Worldwide.
The simple fact is that people* just can't be trusted to do the right thing. In society, we make laws that - at least in theory - try to strike a balance between protecting the few people who are idiots (or protecting everyone from the few that are 'bad') while not unnecessarily burdening or inconveniencing all the normal people.
Unfortunately, in Australia our 'leaders' seem to lean strongly towards the side of law enforcement, enacting laws that affect everyone in order to target a very small group. Like the very strict alcohol laws in Sydney. You can't drink in any public place, you can't buy alcohol after 10pm and bars must shut their doors at 1am and kick everyone out at 3am. Oh, and, we have one of the highest alcohol tax rates in the world of course. (5th or 6th I think.)
Likewise, we have speed limits of 50kph all over the place and plans to reduce them further still. the M2 went from 100kph to a hotch-potch mixture of 70, 80 and 90kph and, following form, the fines keep getting raised well above CPI.
That turned into a bit of a rant but the point is that Australia tends to favour the 'nanny-state' situation, cracking down and affecting everyone to try and catch/stop/help 0.1% of people. So why, when there is a risk like this - of our private and very personal data being misused - do we not apply a similar mindset?
I can't stop in to grab a 6-pack on the way home after a late night at the office because we need to stop the tiny handful of people who want to get viciously drunk at home before heading out for a night of 'alcohol-fuelled violence' but who are also poor planners or don't have much cupboard space and so need to do an emergency run to the bottle-shop for some vodka Cruisers or whatever it is people drink in such situations.
That's apparently okay, but putting in place simple, prudent safeguards, oversight and restrictions to prevent public servants from abusing our personal data to spy on anyone they want is just too much to countenance and so this huge trove of data that is and will forever be available to even the lowliest police officer represents a colossal risk to the privacy and security of every single man, woman and child in Australia.
It's fine to inconvenience the entire population to target a small handful of people but apparently far too much to ask to inconvenience a few police officers in order to protect everyone.
* - I am reminded of a line from Men In Black where Will Smith's character says that "people are smart - they can handle it" to which Tommy Lee Jones's character replies: "A person is smart, people are dumb." Likewise, a person might be trustful but people aren't.