In practice of course you rarely need to go back anything remotely like that far, and only a lunatic would arrive in court citing Magna Carta (and they do. The Acts of Union are another sure sign of a madman.)
I was one of those madmen twice (magna carta) and it worked , (actually that long time muppet Tony Benn told me it was a good approach coupled with the questioning of the validity of the mandate for reforming the rates system) .
Though to be fair it was the challenge to the figures they had used that clinched it .
But your use of the word madman means that I could have challenged them on the third line open (there were only 3 options available to challenge the charge) and that was eligibilty , insanity meant that you were not eligible for Poll Tax .