The Motor Carrier Act of 1980 deregulated the industry, which led to a sharp increase in competition among carriers. Over time, this pushed down freight rates a

The Motor Carrier Act of 1980 deregulated the industry, which led to a sharp increase in competition among carriers. Over time, this pushed down freight rates and put pressure on companies to cut costs at the expense of drivers. Many drivers are now classified as independent contractors rather than employees, meaning no benefits or wage protections. Obviously this also happened against the background of a broader trend towards deregulation that proceeded under Reagan, so it's not just that act.