"In economics, a free market is a system in which the prices for goods and services are self-regulated by the open market and by consumers. In a free market, the laws and forces of supply and demand are free from any intervention by a government or other authority"

If you outlaw pump and dump scams, it's not a free market. I tend towards favoring less government rather than more, but I wouldn't invest in stocks in any sort of free market environment.