'NO GRASSING' But do gang bosses practice what they preach? THOUGH shalt not grass. It's like the eleventh commandment. For those living in areas with high criminal quotas like the East End of London being outed as or labelled a grass would be second only to being branded a nonce in terms of undesirable outcomes.
The phrases "you don't grass" and "nobody grasses" would be drummed into them from birth.
It stems from criminals who are caught not snitching on fellow cons involved in the same job and ensuring that law-abiding people living around the gangsters never spoke to police even if they did know what was going on and who was behind it.
But, this unwritten code of honour does not apply to everyone and is nothing to do with honour among thieves.
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As with many things it is about fear and control.
"You know what happens to grasses" is the warning to say what will happen to anyone who falls foul of the system - it would be met with serious violence or even death.
But, the gangsters at the top who dish out these warnings don't play along and are the biggest grasses of all.
At the mere feel of a finger on their collar they would be spitting out names quicker than a machine gun releases bullets.
In fact, top criminals ensure the likelihood of their collar being felt is very low by proactively grassing on rivals before trouble is at the door.
It may not be done directly by the criminal boss, but his outfit will have a number of registered police informants who give up other underworld figures in the hope that it will provide immunity to their network.
At the same time those conduits between police and crime lords will be trying to corrupt serving officers into leaking any information they want about ongoing enquiries.
A secret Met Police report into collusion between corrupt serving and former officers and gangland syndicates called Operation Tiberius, which I have seen, details exactly how this has been done.
Top-end firms like the north London Adams family had registered informants and corrupt officers working for them.
It is fair to say their organisation would "sing like a canary" if it was to their benefit.
There may be some genuine top-end crooks who would never snitch on anyone, but the criminal world is full of grasses - mostly at the higher end of the ladder.
In the same way that religions were invented by humans as a way of keeping the general population in check, the no grassing code was invented by gangsters as a way of bringing fear and control to the communities they lived in.
The general public fear what will happen to them if they grass and being labelled one by neighbours so the gang leaders are able to control them by ensuring they don't reveal what they are up to.
But at the same time they'll drop you in it as soon as look at you.
And, with its secret network of registered criminal informants the police force is complicit with this coercive control.