When
Marriage Acts are amended to bring same-sex couples within their ambit, those
couples become subject to the existing restrictions imposed by blood and family
ties (consanguinity and affinity) which forbid people from marrying someone too
‘close’ to them. So if a woman can’t marry her brother, uncle or nephew, she
can’t marry her sister, aunt or niece either. Simple, right? As far as it goes,
yes. But not once we consider the rationale behind consanguinity restrictions
and what the application of the ‘marriage equality’ paradigm to them is likely
to lead to.
Admittedly,
the effect of consanguinity on marriage custom is not quite as straightforward as
I have implied above.