Whanganui River, a river of great cultural significance to the people that live along it, was declared a legal person after 140 years of negotiation. This is not the same situation as a machine being declared a person because it responds correctly to legal documents.

Whilst there's no reason a machine couldn't be a legal person, in the sense that the sentence describes a possible future, that future is not near, and it will take more than a competent robolawyer to bring it about.