Bill Browder was in London, watching helplessly.

It was late 2008.

His friend and lawyer, 37-year-old Sergei Magnitsky, had been arrested and thrown into Moscow's

boutierka prison.

This is Browder telling the story to the independent media company London Real.

Up until 2005, Bill Browder had been a hedge fund manager, who worked in Moscow and was

among the largest private investors in all of Russia.

But then, his lawyer, Sergei Magnitsky, had found evidence implicating Russian officials

in massive corruption and also implicated them in having connections with the Russian mafia.

Magnitsky was jailed, held for more than 350 days without trial and killed.

Cause of death, blunt trauma to the head.

When he died, when they killed him, it was so far outside of my own expectations of

the worst-case scenario.

I couldn't even process it.

It was just so horrible.

Well, I processed it the only way I knew how, which was to take responsibility to go after

the people that killed him.

Bill Browder pushed hard.

He has constantly advocated for sanctions against Russia.

And in 2012, he was instrumental in Congress's passing of the Magnitsky Act, which bars

Russian human rights abusers from entering the United States.

Browder is also one of Russian President Vladimir Putin's most-forthful critics.

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