The by laws are at https://wikimedia.org.au/wiki/Rules - 4(5), (6) and (9) give the committee the ability to accept or reject, but don't specify grounds. Policies listed on the site don't mention criteria for accepting or rejecting membership.

I'd love to help but the chapter just rejected my own application for membership without giving reasons and I'm still trying to find out why.

Kindest regards

Andrew