I was preaching and approached a lady. She said "no I do not want to listen" so, I left her. Then I saw some children. As I went toward the children, the lady started shouting. She stood up and threatened me that she would physically assault me. I went back to rebuke her that making threats is unlawful and it is also unlawful for her to tell me where I can go and who I can talk to, if the person I am speaking to has no problem with it.
Her shouting and screaming resulted in a crowd gathering around and one man decided to assault me. I managed to record this lady threatening me on my phone so I have evidence. I also recorded the man threatening me who was the man that assaulted me.
The police were called. And they said: "Even though there is no law forbidding adults to approach children, it is not good etiquette" therefore they will not let me get justice for the assault.
They reasoned that I should let them get off with it and similarly they too should let me off with it (though I did nothing unlawful).
I reasoned with them that this is not the right course. The right course is to do justice, against oneself, a rich person, poor person, one's relatives and friends, and against a large criminal party. I said "if I have done something wrong, it's only right I should be brought to justice and I would rightfully be a witness against myself. If we do not do justice people will just do the crime again."
"The etiquette they follow, is not law and for a good reason as it causes oppression, and I think it is also against Human Rights."
I was told by the police that they were not going to charge the lady or the man or further investigate it, even though I had the evidence to prove my case, as etiquette is above the law.
My question is:
Is etiquette above the law? Is it possible to answer this question both comprehensively and specifically. I am a self-studying law student and would like to understand these sorts of situations in law.
This is in UK.