Best is co-founder of the Institute for Critical Animal Studies (ICAS), formerly known as the Center on Animal Liberation Affairs (CALA), the first group dedicated to the philosophical discussion of animal liberation. His academic interests are continental philosophy, postmodernism, and environmental philosophy. He is the editor, with Anthony J. Nocella, of Terrorists or Freedom Fighters? Reflections on the Liberation of Animals (2004), which has a foreword by Ward Churchill, and the sister-companion volume on revolutionary environmentalism, Igniting a Revolution: Voices in Defense of the Earth (2006).
In December 2004, Best co-founded the North American Animal Liberation Press Office, which acts as a media office for a number of animal rights groups, including the Animal Liberation Front (ALF), though he has said that he is not himself an ALF activist. He came to public attention in 2005, when the British Home Office told him it intended to use counter-terrorist measures adopted in light of the July 2005 London bombings to prevent him from addressing an animal rights rally in the UK. Best responded by alleging that Britain was becoming a police state.
In 1993, he began as an Assistant Professor of Humanities and Philosophy at the University of Texas, El Paso, promoted to Associate Professor in 1999, and then to the Chair of the Philosophy Department in 2002. His colleagues replaced him as Chair in March, 2005, an act which Best has alleged appeared to be a form of punishment for his outspoken activism on behalf of ethical causes such as animal and earth liberation that the academy has largely dodged to date.
In 2005, Best planned to attend a rally to celebrate the closure, as a result of protests from the animal rights movement, of Newchurch Farm, where guinea pigs were being bred for research purposes. Charles Clarke, the British Home Secretary, said he would rely on new Home Office rules preventing people from enter the UK if they "foment, justify or glorify terrorist violence in further of particular beliefs; seek to provoke others to terrorist acts; foment other serious criminal activity or seek to provoke others to serious criminal acts."
In a letter to Best dated August 24, 2005, Clarke cited a comment by Best quoted by The Daily Telegraph: "We are not terrorists, but we are a threat. We are a threat both economically and philosophically. Our power is not in the right to vote but the power to stop production. We will break the law and destroy property until we win." Best is also alleged to have said that the animal rights movement did not want to "reform" vivisectionists but to "wipe them off the face of the earth."
The letter from the Home Secretary said:
In expressing such views, it is considered that you are fomenting and justifying terrorist violence and seeking to provoke others to terrorist acts and fomenting other serious criminal activity and seeking to provoke others to serious criminal acts." The letter was dated the same day that the Home Office published its new list of behaviors that would see people banned from the UK. Under the list, people who write, speak, run a website, or use their positions as teachers to express views that "foment, justify, or glorify violence in furtherance of particular beliefs" will be banned or deported. The British government called the new measures part of its "ongoing work to tackle terrorism and extremism."
Best responded to the ban by saying it didn't surprise him. He told the Chronicle of Higher Education: "It was only a matter of time, especially after the July 7, 2005 London bombings. The climate in Britain is totally unbelievable. It's very fascist. It's becoming a police state."