National City Lines was formed in 1936 as a holding company, for the express purpose of acquiring local transit systems throughout the country, mostly in medium-size cities. Many of those transit systems had already converted from streetcars to buses. But the controversy involves those transit systems which were still running streetcars when acquired by NCL. The conflicts of interests are apparent.
Apologists for corporate interests generally claim that the conversion to buses would have occurred anyway, but NCL's illegal practices while carrying out this conversion are court documents.
It is possible that federal legislation in President Roosevelt's New Deal instead that killed the streetcars, and not the documented NCL conspiracy. Because streetcars were the earliest heavy users of electricity, it was practical and economical for many streetcar systems to be owned by the electric utility companies themselves. But rural electrification was less profitable for the utility companies and there were feelings of neglect in rural America. So in 1935, as part of the New Deal, federal legislation was passed, ordering the electric utility companies to sell off their businesses not actually providing electricity.
Suddenly, these streetcar systems became more readily available for takeover by NCL.
See also General Motors Streetcar Conspiracy