Washington, D.C., became the largest U.S. city to pass a law making public buses free to riders.   Washington, D.C., became the largest U.S. city to pass a law making public buses free to riders.  The legislation, which was passed by the city council earlier this month, will eliminate the current $2 fare starting this summer. More: The bill was not approved by D.C. Mayor Muriel Bowser, but the City Council enacted the proposal without her support last week.  The legislation adds a dozen 24-hour bus lines starting in July and calls for a $10M investment into the city's bus line and public transit infrastructure. The city council is now debating whether to add an amendment to subsidize rail travel for D.C. residents.  Zoom Out: Kansas City passed a law making its bus system free in 2019. Cities and municipalities across Europe are increasingly offering free or heavily-subsidized public transit as a way of minimizing harmful emissions produced by cars.