(Coverage of Victorian by-elections tonight from 6 pm. Live page will go up around 5 pm).
Initially this system lacked obvious downsides but its potential for exploitation was obvious as early as the 1987 federal election, where a Nuclear Disarmament candidate with 1.5% of the primary vote was elected. A series of farcical GTV elections around the country since led to the abolition of the system in NSW, federally, SA and WA leaving only Victoria. Problems exposed with the system have included:
* parties winning off tiny vote shares defeating much more popular parties when they would not win under any other system
* confusing and deceptive GTV preference allocations that are beyond the understanding of most voters if they tried to follow them
* preference harvesting in which ideologically unrelated parties band together to try to secure election off each others' group ticket preferences
* creation of unnecessary tipping points that should be irrelevant to the contest, making it easier for elections to be voided (eg WA Senate 2013)
* creation of bogus near-100% preference flows between parties when, if asked to choose preferences for themselves, voters spread preferences in a much less concentrated fashion
* corruption of parliamentary voting behaviour, in the form of party votes on electoral reform being influenced by fear of losing the ability to work with Glenn Druery, as stated by Druery himself in the Angry Victorians sting video
* denying voters the ability to direct their own preferences between parties above the line (which they will be used to doing so having done so twice since the last state election) and throwing away their stated preferences and overwrites them with a group ticket vote if they do.
*confusion between the Victorian system and the Senate system