in line to throne

[Dom Tuk]

what are the legal implications if a member of the British royal family who is in line to the throne has his/her parentage disputed.

[bernardo]

The law assumes that all children born to a married couple are legitimate unless proven otherwise.  If there were to be a serious claim made to the contrary, then it could be contested in court and DNA would prove the answer.  This would probably depend on action being brought by a rival claimant.  A similar incident occurred about a decade ago when the current Lord Moynihan (the former MP Colin Moynihan) succeeded the fomer Lord Moynihan when it was proved that the former Lord Moynihan's wife's son was not in fact his.  (Another son of the former Lord Moynihan was also disqualified on the grounds that his mother had not been properly legally married to him at the time).

 

If there were to be such a case, then the practical implications would be that the person concerned would no loger be in line to the throne.  It would, of course, be possible (albeit extremely controversial) for Parliament to restore the situation by passing a law to proclaim the would-be heir to be legitimate anyway, or to be a valid heir as if legitimate.