No justification is required because it's pretty much baked into the mentality of the Midwest. The auto industry is what drives the Michigan economy (at least its most populous areas). Therefore most constituents not only don't mind, but likely fervently support such laws. The same could be said for the United Auto Workers. Pretty much the opposite of the free market, yet most people in Michigan support it because either they or somebody they know relies on the benefits created by the union.

Further, few people in Michigan can afford a new Ford, let alone a $60,000 electric car. If Tesla wants to lobby for free market economics, Michigan is probably the very last state they should be trying to convince.