‘We are following the science’ is the claim UK government ministers have repeatedly made in justifying their decisions on how to deal with the COVID-19 pandemic. These decisions include when to begin and end stringent social distancing and whether to tell people to wear face masks. Ministers get this advice through a complex network of scientific advisory committees. But to rely on science as the determining influence on policy is to misunderstand what science is. And the process of organising knowledge for policy through advisory committee is political, as well as scientific.