Keep your child from bad company
Your child is mixing with the wrong kind of people. Understand what's happening and know how to deal with the situation.
Children usually gravitate towards bad company when they suffer from a poor self image. The cause of this can be difficult to determine and a full psychological assessment may be necessary. Generally if a child grows up in a positive environment with positive parents, he ought to develop a positive self image and mix with an encouraging peer group.
The other reason a child mixes with bad company is because he is bad company. If you allow your child to treat you with disrespect, then he will grow up to be disrespectful and arrogant. You need to monitor the little things, like the feedback you receive from other parents after play dates, the way he treats his friends, his family and your home, believing he can do as he wishes without consequences and that the rules don’t apply him, etc.
Eventually he may end up alienating his friends and find that the only children who will put up with him are other boys and girls who are badly behaved. Once your child gets into bad company in this way, it is difficult to break the cycle. Case histories show that most teenagers in trouble were trouble at nursery school, trouble at primary school and trouble at high school. So your child needs to grow up knowing that there are rules and when they are broken, there will be consequences.
If your child has begun mixing in bad company you can refuse to allow such friends to visit your house. What you cannot do successfully, is to ban him from mixing with these friends outside of your house because you are simply not able to control this.
Many parents attempt to do this and lose credibility as far as discipline is concerned. As with most things in life prevention is better than cure: therefore your child should grow up feeling loved, respected for who he is and should know his boundaries.