I’ve seen how oxycontin wrecks lives – why have the Sackler family members behind it avoided all charges? | Laura Poitras

I filmed as activists held Purdue Pharma's owners to account via museums and galleries. Yet the US government has utterly failed to play its part

Among the outstanding films nominated for an Academy Award this year is Argentina, 1985, about brave young lawyers and victims of Argentina's brutal dictatorship who prosecuted the military leaders responsible for the mass torture, rape and murder of thousands of civilians. They faced down death threats, risking their lives to testify against the perpetrators in power.

The film bears witness to a simple truth: a society that does not confront its crimes is condemned instead to repeat them, and to reward those who commit them.

Laura Poitras is a filmmaker and journalist. Her films include All the Beauty and the Bloodshed and Citizen Four

Do you have an opinion on the issues raised in this article? If you would like to submit a letter of up to 300 words to be considered for publication, email it to us at guardian.letters@theguardian.com