I had the opportunity to go to one of the three in Ghana, all located in the Northern Region. It's a place where people who are decided to be witches are sent. It is believed they may be cured by the Fetish Priest. But even so the're likely not given a warm welcome home. I did some taping, some interviews. When asked why they are there they say Hate. It's a prison with invisible bars.
I asked Abdulai about witches. He said there was one in Voggu who killed his bestest friend. He had to leave the village for 3 months to get over it. He told me the story though he said I would have to see it to believe it.
Basically there are certain people in the village who "know" about witches. One of those people declared a meeting with all the women in the village and said that one person there was planning to kill a young man (at this point Abdulai said is this scaring you? - I said no) and if that person went through with it that they would be caught. That night Abdulais buddy got a headache, but they thought it just couldn't be him and that couldn't be a sign. But it was and then a few hours later he was dead. Totally dead.
So the next day all the women were called again and the man declared that the woman was not present. He went to her house and went into her sisters room - that is where she hid the juju, (living in the same house as the boy - his Aunt) there was a thing that he found in that room that no one else could have noticed. It was a strange looking thing with hair and human blood in it. There was also a tooth and a woven piece of rope like for catching a fish. The woman was sacked to Dalun, a fairly nearby village that has a body of water and a fetish priest. It is said that if the witch tries to kill again the water will kill her.