Hmm, something not quite right here I don't think.
Apparently he had a previous terrorist conviction and was out on licence and wearing an electronic tag following his release.
He was from Staffordshire, so surely it would have been flagged up that he was now in London and in the vicinity of London Bridge wouldn't it? He was apparently attending this prisoner rehabilitation conference where the attack happened . Wouldn't they have checked all attendees for weapons and knives upon their arrival?
This seems like it should have been preventable.
And anyway, in 2013 he received a fixed term sentence of 16 years, whereby he should have served at least half his term. Half of. 16 is 8 and 8 added onto 2013 is 2021.
Seemingly they must have been convinced he had been rehabilitated to a degree in order to allow him to attend this event.
Definitely questions to be answered here.