For decades, if you wanted a divorce in Australia, you had to prove your spouse was to blame. No-fault divorce was not legal by local law. The grounds ranged from habitual drunkenness to adultery, and many cases involved the use of private investigators.
Some couples who privately agreed to separate would even have to stage adulterous trysts for later evidential use in court. This all changed in 1975 with the introduction of “no-fault divorce” and the Family Court system.