Of course, why let a bunch of time-honoured law get in the road of a legal prosecution...?
You have misunderstood the legal standing of Para 29 or 39 in some later Charta.
It is available in modern legislation only to the extent that the particular soveriegn state has allowed.
Numerous attempts have been made by litigants, many of them representing themselves, to argue that local legislation that conflicts with or which seems to override Magna Carta is invalid. This argument seems to be based on the premise that the fundamental constitutional character of Magna Carta operates as if it were a constitutionally entrenched provision to which all local enactments are obliged to conform.
Read more here
The Icon of Liberty: The Status and Role of Magna Carta in Australian and New Zealand Law - [2000] MULR 34; (2000) 24 Melbourne University Law Review 866