Everyone in San Quentin calls him Wall Street. Curtis Carroll aka Wall Street teaches his fellow prisoners about stocks. Through friends and family on the outside, he invests and he’s also an informal financial adviser to fellow inmates and correctional officers.

When Wall Street was put in prison almost two decades ago he couldn’t read or write. One day he stumbled on the financial section of the newspaper thinking it was the sports section, which his cellie used to read to him. An inmate asked him if he played the stocks.

“I had never heard the word before,” says Wall Street. “He explained to me how it works and said, ‘This is where white people keep their money.’ When he said that I said, ‘Whoa, I think I stumbled across something here.’ ”

Wall Street taught himself how to read and write beginning with candy wrappers and clothing logos. Today he pores over financial news: the Wall Street Journal, USA Today, Forbes. Business is like a soap opera, he says, and he’s always trying to anticipate what will happen next. “I like to know what the CEO’s doing,” he says. “I like to know who’s in trouble.”

Wall Street doesn’t have access to a computer or the Internet, so he calls his family members to check the closing prices for the day, and he tells them what to buy.

“I’m in prison, but I’m on just the same playing field as Warren Buffett,” Carroll says. “I can pick the exact same companies. I can’t buy as many shares, but technically we’re just the same.”