I can help you with that. A hoard of lawsuits started being filed against people who fraud-ed people using crypto's. In order for the people who were ripped off to be able to proceed in court for losses the federal chairman had to make a determination that crypto's held value, he determined that crypto's hold the same value as any other fiat.
https://www.sec.gov/news/testimony/testimony-virtual-currencies-oversight-role-us-securities-and-exchange-commission