Uber, no stranger to controversy over the safety and business practices of its on-demand ride service, is under new scrutiny after deadly shootings Feb. 20 in Kalamazoo, Mich. One of its drivers, who took Uber fares just before and after six people were killed and two were wounded, was arrested that night and is charged with the random street murders. The San Francisco-based company's screening of drivers is being questioned. "Its handling of the crisis and ability to make passengers feel safe could have a greater impact on the company's future than its many battles with government regulators," says a CBS online article.

This is the latest headache for Uber, which has spread globally since starting in 2009. Passengers use a phone app to book rides and pay via credit card information on file. A car typically arrives within minutes and fares generally are far lower than for traditional cabs. But earlier in February, the company agreed to pay $28.5 million to settle class-action lawsuits that claim it misled consumers about fees and driver background checks. One policy drawing complaints is automated "surge pricing" that boosts everyday rates at times of peak demand or a shortage of available cars, such as weekend evenings, during foul weather and even in cases of natural disasters. Other complaints involve an inability by some of the part-time drivers to find destinations.

In addition, some government regulators – often prodded by taxi drivers – have tried to restrict local operations, require vehicle inspections or impose taxes and license fees similar to those cab fleets pay. Without having to meet the same standards, critics say, Uber competes unfairly and may use drivers who're untrained and possibly uninsured. At the same time, Uber's success brings competition from other ride-sharing startups using smartphone apps. The biggest is Lyft, which launched four years ago -- also in San Francisco.

Uber backer says: "Criticism that's being leveled at Uber is more a function of Uber being a disruptive technology." – Edward Davis, past Boston Police commissioner who is on Uber Safety Advisory Board

Critic says: "An HR [human resources] person from Uber should be meeting with prospective drivers before allowing them to drive. . . . Drivers, similar to daycare workers, are placed in a position of trust." -- Dave Sutton of Who's Driving You, a taxi industry campaign

PR specialist says: “Uber needs to talk about the process it uses to connect riders and drivers, reinforcing all the things that they do right.” – Mary Ann Sabo, communications adviser, of Grand Rapids, Mich.