Driven to Despair: Doug Schifter waged a one-man campaign to stop Uber from putting his fellow black-car drivers out of business. Then he decided to take his own life.

For a black-car driver like Schifter, it was not a good time to stumble into a financial crisis. Not long after its founding in 2009, a San Francisco start-up called Uber went looking for new markets to conquer with its app-based ride service — and New York’s antiquated, dysfunctional taxi system made it the perfect target for disruption.