22 arrested doesnt mean 22 guilty.
What ever the background checks made, the employers can only go on the checkable evidence provided to them, they pass that on to the BAA who would have made their own checks and then decided who passed the required standards to be eligible for the appropriate security clearance.
I know pilots/atcos and other "professionals" who have convictions for a wide range offences, but although declared vis security protocols, it hasn't precluded them from gaining airside access.
Just because someone is arrested it doesnt mean that they should be hung drawn and quartered by Burn and his his friends in their balck & white world, before the facts are proven.