have been rearranged in SA, so that for next year's state election we are now in Badcoe, which previously didn't exist and seems to have been created by chopping adjoining corners out of 4 other electorates.
I was in a new federal division at this year's election (Burt) so there was no sitting member to vote for. The Labor candidate spent an awful lot of time at our early posting centre though, the Liberal one not so much. Coincidentally Labor won this seat.
Seems a bit wrong that electoral districts can't just follow a straight course though and cut in and out to create this sort of bias. How do they get away with it?
...because in the US the boundaries are mostly decided by a partisan committee. Let me know when you find any way this could possibly go wrong.
Yes, in the US they're normally done by state governments, with only a handful of states having independent electoral commissions.
South Australia has a different problem - the legislation actually requires boundaries to be set to maximise the chance that a majority of votes = a majority of seats, but at the moment it's almost impossible to achieve in practice, meaning that Labor has won the last two elections with less than 50% of the two-party vote. This is partly because there are Labor-supporting independents in seats which Labor probably couldn't win themselves, but mostly because lots of Liberal votes are wasted in ultra-safe country seats but there are only small pockets (mostly around Port Adelaide) which are similarly safe for Labor. (In Victoria it used to be the other way round - lots of Labor votes locked up in the northern and western suburbs - although less so now).