Their seems a much more obvious choice that does not imply an assumed gender.
"Their" is the clumsy workaround used by people who don't buy into the Interpretation Act 1850 and its successor legislation, but who are happy to use plural pronouns to describe singular individuals.
"Their" is the clumsy workaround used by people who don't buy into the Interpretation Act 1850 and its successor legislation, but who are happy to use plural pronouns to describe singular individuals.