In cases where paternity is questioned, I think that parents asking for child maintenance should be required to pay for DNA tests to prove relation to the paying parent before child maintenance services can take money from the other parent.
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Currently, it is the duty of the person who denies relation to the child to pay for the DNA test. The Child Maintenance Service will refund this if it parentage is not proven, but I think it should be responsibility of the parent asking for maintenance monies to pay for the test in the first place. In cases where the CMS don't assume parentage, the responsibility falls on the person being asked to pay to prove they are not the child's parent. If they cannot pay for the DNA test to prove this, they have to pay maintenance fees. I think it should be the responsibility of the parent asking for financial support to fund a DNA test to prove relation with the other parents where this is disputed.