Pre-emptive censorship again. Cancel yourself before someone does it for you.

A documentary that lifts the lid on a “race science” network of far-right activists in Britain and its links to a rich American funder of eugenics research has been pulled from the London Film Festival (LFF) at the last minute due to safety concerns.

The organisers have taken the “heartbreaking decision” to cancel the planned screening of the “exceptional” Undercover: Exposing the Far Right this weekend due to fears about the welfare of the staff and security working in the festival venues.

Thus sending a message that merely threatening to make a stink will inspire the people in charge to cancel everything just to be on the safe side.

Havana Marking, the director of the film – which made headlines last week for identifying the backer of research into so-called race science and highlighting the racist views of former London mayoral candidate Nick Scanlon – has criticised the decision to pull the premiere as “a very unfortunate outcome”.

“I understand the festival need to look after their staff, but I am furious that our film has lost a planned theatrical release so late in the day,” she said. “We were told the LFF felt they could not show it due to security issues. I do feel, though, that the power of the far right is exaggerated, although their influence is clearly dangerous.”

Erring on the side of cancelation sends the message that mere shouting can get panicky organizers and publishers and universities to shut everything down.