What do you personally feel is the greatest social offence one can commit?

Today, in our English class we looked at different social offenses one can commit such as lying to parents, killing someone for revenge, selling drugs, crashing a party, etc... From these offences, I personally feel the greatest social offence one can commit is killing someone for revenge. This is the worst social offence I find in today's society. In my opinion, I think that killing someone for revenge will not solve anything. It would just make the matter worse and will create huge problems like ending you up in a jail. No matter how big or small the problem is, you should never go that far like murdering people. I think that killing someone is the worst solution you can ever think of. For me, even killing a small insects by mistake makes me feel bad. I could never imagine killing a human. I believe that there are different ways you can take revenge besides murdering. Therefore, I believe that killing someone for revenge is the worst social offence one can commit.