Impartiality test

Thatcher very much did pursue the poll tax which was widely and rightly seen by most of the public as grotesquely unfair. In fact, her refusal to budge on the issue with her usual trademark stubborn arrogance was so clearly leading the Tories to disaster that it became a major factor in her own MPs toppling her. 

She did pursue it and refused to stop pursuing it in spite of it being widely seen as grotesquely unfair, the poor being expected to pay the same as the rich. It was because of her refusal to cease pursuing it that the party was heading for defeat. They had to ditch the policy and replace it with something fairer to save their government. She was having none of it and so they had to remove her to ditch the policy.

The more rigorously they enforced something so grotesquely unfair and unpopular, the more disastrous it would have been electorally for the Tories. And she failed, albeit only just, to get enough votes in the first round of the leadership ballot to avoid a second round. And it was made clear to her by everyone that mattered that she would lose that second round vote. So her only choice was to jump or be pushed. And her stubborn stupidity over the poll tax was a major cause of this.

And yes they were elected on a manifesto promise to replace the rates with something fairer. But instead they replaced them with something so grotesquely unfair that a large majority of the public were intensely angry about it. Had she accepted that she was wrong and backed down, she'd likely have survived and possibly  led the Tories to victory in 1992. That she refused to give a stuff about what the public thought meant only that she was guaranteed to lead her party to disaster if she stayed.

And the poll tax itself was made virtually unworkable by the mass resistance of much of the public refusing to pay in a campaign of civil disobedience, which utterly overwhelmed those whose job was enforcement. Private tenants in particular kept changing address to avoid payment. I myself am proud to be one of those who refused to pay and refused to cooperate with registration forms of any kind. The council tax is far from perfect and itself highly regressive but was enough of a nod in a fairer direction for most people - including me - to cooperate in paying it.

One of the poll tax enforcement problems was  that many of the very poorest who never paid rates, had to pay 20% of the poll tax. Hardly any of them did and the cost of enforcement in such cases would have been far greater than the sums collected. An obvious factor that should have been foreseen but typically wasnt.