Maryland has booted more than 4,000 of the state’s ride-hail drivers off the roads since December 2015, because they failed to meet the state’s screening requirements, despite passing Uber and Lyft’s background checks, according to the Maryland Public Service Commission.

The commission, which regulates ride-hailing in Maryland, said 6 percent of the app-based drivers have been booted since the state began processing ride-hailing applications at the end of 2015. The vast majority — nearly 97 percent — were driving for Uber, commission spokeswoman Tori Leonard said Monday. The review included 74,000 drivers.

Leonard said drivers can be rejected for a multitude of reasons, including criminal and driving history issues, failure to verify identity, too little driving experience, and being on a limited-term temporary license. The state doesn’t conduct its own background checks, but rather, processes applications, reviewing information provided in Uber and Lyft’s reports for compliance.

Leonard said a “good portion” of the rejections dating back to 2015 were not for criminal or driving-history related reasons, meaning they “would not present a safety issue,” but it was unclear if that pool made up a majority.

Uber said the PSC’s criteria for determining compliance often relied on subjective factors, rather than objective criteria. But it lauded Maryland for adopting new rules for vetting drivers earlier this year.

A breakdown of the rejections was not immediately available. The Boston Globe first reported the Maryland figure in a story that weighed Massachusetts’ ride-hailing background checks against other states’ screening methods.

Uber derided Maryland screening requirements as too vague in an August letter to the commission.

The “Commission’s regulations do not contain specific criteria to determine whether an individual’s criminal history should preclude them from operating as a [driver] in Maryland,” read the  letter from an Uber attorney. “Instead, the Division utilizes non-public guidelines for this review.”

Maryland later adopted an alternative screening process with more specific requirements, which would allow Uber and Lyft keep operating in the state without conducting fingerprint-based background checks preferred by some law enforcement officials. Uber had threatened to leave Maryland if fingerprint screening was mandated.

Instead, Maryland regulators said the ride-hailing companies should subject drivers to screenings that encompass their entire adult life — rather than simply going back seven years — and address concerns about identity verification, the comprehensiveness of record searches, and timely follow-up requirements.

The revelation that thousands had been disqualified from driving, despite meeting Uber and Lyft’s initial requirements, was fodder for those who say ride-hailing companies are too lax in their screening.

Massachusetts has banned more than 8,200 of nearly 71,000 drivers who had already passed ride-hailing companies’ background checks, according to the Globe. Among them were 51 registered sex offenders and hundreds of others who were barred for sex-related crimes and violent incidents, the Globe reported.

It was unclear what proportion of drivers booted in Maryland were disqualified for safety reasons. Lyft said its drivers were most often disqualified for licenses marked “not acceptable for federal purposes” — a type of license issued to immigrants living in the country illegally, among others.  Still, the removal of thousands of drivers renewed concerns over the the efficacy of Uber and Lyft’s vetting.

Dave Sutton, a spokesman for ‘Who’s Driving You?’, an initiative of the Taxicab, Limousine & Paratransit Association, said the results prove government and FBI-approved checks are superior to Uber and Lyft’s screenings, despite the companies’ claims to be as or more effective.

“It’s completely unacceptable,” Sutton said. “I mean, government checks are clearly superior to private checks … Uber has been notoriously sloppy in so many aspects of its business. It’s not surprising the fault was found more there.”

The Virginia Department of Motor Vehicles did not respond Monday to an inquiry on whether similar issues were found under its ride-hailing law, which went into effect in mid-2015.

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