There's no monkeying around when it comes to legality. Though copyright law gets a little murky when it applies to a photo taken by a monkey.
A British photographer is considering legal action against Wikipedia and Wikimedia Commons over the rights to a selfie taken by a Macaca nigra with his camera, as ABC 7 reports. Wikimedia claims that because the photo was taken by a non-human, they could not fulfill David Slater's request to take down the photo.
Wikimedia Commons responded with this statement:
"A photographer left his camera unattended in a national park in North Sulawesi, Indonesia. A female crested black macaque monkey got ahold of the camera and took a series of pictures, including some self-portraits. The pictures were featured in an online newspaper article and eventually posted to Commons. We received a takedown request from the photographer, claiming that he owned the copyright to the photographs. We didn't agree, so we denied the request."