While saying there was "no question" the man had the mental capacity to use condoms, Court of Protection Justice Eleanor King said the sterilization was "lawful and in his best interest," The Daily Telegraph reported Friday.
The man, identified only as DE, has a mental age of between 6 and 9. The judge said the man and his girlfriend, who also has learning difficulties, almost broke up from the consequences of having a child in 2010.
The child is cared for by the man's mother, and King said it was "inevitable" the mother would also have to care for any future children DE might have.
DE has said he does not want any more children.
Angus Moon, an attorney appointed to represent the man, termed the case "truly exceptional" and denied the ruling should be seen as a signal for the mentally disabled to be forcibly sterilized.
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