Did I have the right to ask them to leave my property, especially after being so rudely told to remove myself?

During an investigation of an accident and injury to a lady, my son was seeing the police officer asked my wife and I to remove ourselves from the scene and stand on our porch. To make it short, by this time our son was in handcuffs and inside one of the patrol cars. The lady’s sister had arrived on the scene almost at same time the police did, she called the police. She insisted my son had hit her with his truck or used force of some kind. My son's girlfriend the whole time said she had fallen off his trailer and injured herself. Anyway, when he asked us to go away, I told him if he wanted a private conversation with them he could step off my property and do it, which angered him severely and he said we were interfering with a police investigation. Neither my wife nor I had said one word but only listening to hear why our son was being detained. I told them this was my property and to remove themselves. They both charged at me trying to intimidate me. I stood my ground, didn't cower down as they expected, but did not assume a defensive posture either. The police officer very loudly said I was interfering etc., and I told them I was not interfering with anything, that they could talk off my property. He got loud again and aggressively stepped toward me, trying his intimidation tactics once again. The other police officer piped up and said, "I own this property while an investigation is going on!" My wife and I saw this was going downhill rapidly and retreated to our porch. The incident did not happen at my residence or on my street. It happened at another location, they drove over to my house where my son lives with us. The vehicle was on the street, not in my driveway or on the property.