Cass Sunstein has been nominated by the President to head the Office of Information and Regulatory Affairs at the Office of Budget and Management. Sunstein believes "that animals should be allowed to file lawsuits 'with human beings as their representatives'."
I say let them file, but only if they have their own non-human representatives. Only then can we tell if they are really interested in suing.
...And maybe they could wear human suits while suing humans.