goods and service. it's people who are designers, computer programmers, people preparing taxes, accountants, making tens of thousands of dollars, but who prefer to do it off the books. >> this is a professor of sociology and columbia university. he devoted his entire career to studying the criminal side of the u.s. economy, but a growing number of americans working in the shadows are not typically what come to mind when you think of a criminal. >> they may have skills and what they are doing with those skills is not applying for a job in a formal sense but offering their services to people who might pay for cash or give them another kind of payment and they won't report that money to the government. that's where it become as shadow economy is they don't report the wages. >> today's labor market has changed. in a bid to cut costs and stay profitable, companies increasingly rely on skilled freelance labor. p even in the legitimate economy. >> we see this is this huge