However wigglebum is correct. Does the parent have parental responsibility (either via court order or marriage)?
If not this can be applied for, and it would be in their favour to pay maintenance as the judge wouldn't take too kindly to a parent who doesn't.
However this isn't to say that a parent shouldn't have contact with their child if they don't pay. It is rather like treating a child as a commodity and a pawn.
Are you talking about paying child support or paying maintenance to you? My husband pays child support to his ex and was paying maintenance to her until she found a job then it stopped.(not the child support) We get the child every other weekend and 2 weeks in the summer, and the weekend we don't get the child we get to spend 4 hours after school on a day she allows us. We share holiday's and birthdays. Every child need a father in their life (mother also) I don't know what your situtation is but I do know if they pay they get to see them.
My husband has always paid child support. He didn't see his daughter for almost two years, and even when it was sorted through the court contact has always been erratic.
Child support/maintenance & contact are two separate issues. There are many 'absent' parents who pay maintenance and don't see their children through no fault of their own.
Maintenance and contact are two completely separate issues. The courts don't use the term ' a legal right to see their children' but rather ' whats in the best interest of the children taking into account their wishes in light of their age'.