Law it's not biased a priori towards humans.
If a hypothetical strong AI could pass the Turing test our Law would accept it.
Actually there are political groups that want to give legal status to some primates. But always failing...
First you use a hypothetical for your argument, saying that if a hypothetical AI was strong enough Law would accept it. (I'm sure most here will not accept a hypothetical as main argument.)
Then you use an example of intelligent primate legal status cases failing to prove another point. Seems contradictory. Primates are very smart. Primates are also biological; some would say this is a huge difference.
See below:
"A New York Judge Has Granted Legal Person Rights To Chimpanzees [Updated]"
http://io9.gizmodo.com/a-new-york-judge-has-granted-legal-person-rights-to-chi-1699160192
"Ganges and Yamuna rivers granted same legal rights as human beings"
"India has officially recognized dolphins as non-human persons, whose rights to life and liberty must be respected."
http://m.dw.com/en/dolphins-gain-unprecedented-protection-in-india/a-16834519