Torture by girl friend's father

KINDLY GUIDE US: One of my friend, Rakesh was in a relationship with a girl since feb 2014. They had very good relation. They had physical relation as well. That girl was pregnant and they had abortion as well in 2014. After 2 years of relationship my friend Rakesh noticed in jan 2016 that the girl is cheating and not honest as she started loving someone else. Rakesh felt cheated and decided to tell all these to that girls father, as they were relatives. But prior to this , that girl provoke her father against Rakesh in order to hide her all affairs. And the consequences went wrong. That girls father came with 15 people in a bolero to Rakesh's home and humiliated him in front of his family members and few of them slapped, beat him and threatened him to kill him. Since then my friend is totally depressed. I know he is honest. Never cheated the girl. Loved her truely. He is very sad as he is embarrassed in front of his family. I told him to to fight legally but he fear as they are from political background. How can i bring justice for my friend ?? Kindly suggest please.....