In 1989, there was a three-week ban on fluoride in Canberra's water supply following a review into the effectiveness of the mineral for oral health. Following what was described as public outrage at the Legislative Assembly's "indecent haste" in banning the substance, the decision was overturned, in favour of conducting more research into the substance.

This ban was the result of the ACT Electricity and Water (Amendment) Act, introduced by No Self Government Party MLA and speaker David Prowse.

David Prowse was a vocal anti-fluoridation activist. His involvement with unproven medical practices and pseudoscience extended to his career as a naturopath.

His initial motion was lost 12-5, but a new motion by another minor party, The Residents Rally, put forward a motion against fluoride which passed.

The chief minister, Rosemary Follett told The Canberra Times the incident taught MLAs it was "best to consider very carefully the implications of their actions when other members attempt to offer reasoned advice".

Then-Liberal MLA Gary Humphries, said he regretted the brief ban on fluoride, and felt it had tarnished the reputation of the assembly.

Fluoride is a common additive in toothpaste and other oral treatments which helps strengthen tooth enamel. This prevents the devastating effects of tooth decay. After extensive studies into its safety, fluoridised water has been proven to be safe.

This small tidbit of ACT Legislative Assembly history is a reminder of how politics can obscure objective facts about science and medicine.

See: https://trove.nla.gov.au/newspaper/article/122093359