In front of them sat experts from campaigning bodies, transport research and the police - all ready to get into a proper discussion - and yet the MPs demonstrated that they didn't even know the most basic of facts.
Evidence and statistics were bypassed in favour of opinions and anecdotes on sideline topics.
Such a clear demonstration of lack of research and understanding at this level of seniority would, in any other business, be classed as negligent.
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The terror attack carried out by Khalid Masood at Westminster that left four people dead lasted less than two minutes say police.
Two knives were found at the scene in Islington, North London, and the suspects fled on foot before being arrested.
The family of the police officer who was murdered in the Westminster attack have thanked those who were with him 'in his last moments'.