What can I do to help my son and his criminal charges?

I have been trying to find help for my son. I can say his civil rights were violated and there is also an instance of police corruption. This suspect #2 that fled from a serious crime scene should have been arrested but they went out to question him on the following day. The morning of my son’s arrest I called her and she was staying at a relative that lived around the block from the park where this crime took place. She tells me, her cousin was there in morning and had this toy gun in his waist of pants. I ended up finding a lot of helpful information of my son’s defense by my son’s girl whom is cousin to suspect #2. We also find out this suspect #2 had been in prison for rape, robbery assault. But he was made a deal back when in prison facing all these charges. I'm a single mother whose only source of income is social security.