Recent test purchases by Barking and Dagenham Police and Trading Standards found that five out of 13 shops sold potentially lethal knives to a 14-year-old boy without asking for proof of age.
But a legal loophole all too often allows them to escape prosecution.
Stores can argue they are not responsible for the actions of their staff because they have given them training and put up warning signs on tills - a defence known as due diligence.
The POST is backing calls from Barking and Dagenham Council and Dagenham vicar Steven Hanna and to get this law tightened up.

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