Technology that can survive a “Rubber-Hose attack”

manpreet Best Answer 3 years ago

In the documentary film Citizenfour, Edward Snowden says about documents:

I'm comfortable in my technical ability to protect [documents]. I mean you could literally shoot me or torture me and I could not disclose the password, even if I wanted to. I have the sophistication to do that.

What technology/methods exist that would enable the scenario Edward Snowden is referring to when he claims to be able to create a protected file where he cannot disclose the password?