I took part in a demonstration against the Poll tax, which was about to be introduced into Scotland the following year. Aside from it being a horribly unfair tax (the poorest people were taxed more because they tended to be living with more people in one home, and the richer taxed less as this tax was per person and did not take into account how many or how valuable homes were) we were also furious that Scotland was being used as a guniea pig to try it out before it was introduced into the rest of the UK in 1990. There were eventually street riots in London and many believe the failure of the poll tax was the death knell of Margaret Thatcher's premiership.
I also joined a thing called the Scottish 100, a list of 100 prominent Scottish artists, politicians, clergy and all sorts who just refused to pay the poll tax. I eventually paid the equivalent once it had been abolished.