"No background process would have made a difference in this case because the person had no criminal history," Uber's chief security officer, Joe Sullivan, told reporters in a conference call.

Uber uses Checkr, which looks at a person's criminal history for the past seven years. The ride-service company has maintained that all background checks available today contain flaws, even though fingerprint checks are considered by many law enforcement, transportation and taxicab industry officials to be the "gold standard."

The kind of background checks Uber uses are the same kind of screenings any company might do on a prospective employee, but not for someone being placed in a position of trust, said Dave Sutton, the spokesman for Who's Driving You, a public safety campaign of the Taxicab, Limousine and Paratransit Association.

"Not all background checks are alike," said Sutton. "What we're really talking about are fingerprint-based background checks conducted by government."

Sutton said the vast majority of large U.S. cities require fingerprint checks for taxi drivers, who have been arguing that ride services should face the same kind of background checks and training that they do.

Uber recently announced it would settle two lawsuits for $28 million that accused the company of misrepresenting its background check process as "industry-leading." The district attorneys of San Francisco and Los Angeles also filed suit against the company for "misleading and false" statements about its screening process.

When those prosecutors filed an updated complaint against Uber in August, they noted that there were 25 cases in Los Angeles where Uber's background check process failed, allowing registered sex offenders, identity thieves, burglars and a convicted murderer to become drivers.

"The private background check companies employed by Uber do not have access to (California Department of Justice) and federal databases of criminal history repositories," the district attorneys' complaint stated. "The background check companies employed by Uber search for criminal convictions in commercial databases that do not index their records by unique biometric identifiers."

Uber contends that fingerprint background checks are not 100 percent accurate, and can include people not actually convicted of the crimes they were accused of, a point the two district attorneys have also called "false and misleading."

“Our problem with fingerprinting is, we think it’s discriminatory, meaning there’s a lot of people who might have been arrested who were not convicted that will be denied this opportunity,” Uber senior adviser David Plouffe said this week, according to the Boston Herald.

Uber recently announced that it would give people convicted of nonviolent felonies whose crimes were reduced to misdemeanors under California's Proposition 47, an opportunity to drive.

'It's one thing to sign up online in a couple of days. It’s quite another to be fingerprinted and go down to the police station.'

Sutton believes the reason Uber is opposed to fingerprint checks is that half of Uber's 400,000 drivers in the U.S. are part-timers, driving less than 10 hours a week, and many would rather not go through the process of getting fingerprinted.

"The companies are convinced that these people who drive casually will not bother to sign up if it's too cumbersome to do so," Sutton said. "It's one thing to sign up online in a couple of days. It's quite another to be fingerprinted and go down to the police station."

Current California regulations require ride services to conduct criminal background checks that go back seven years, but not fingerprint checks. Sutton believes regulators have been slow to require a stricter screening process because of Uber's political power and success in beating back tougher regulations.

One of the biggest regulatory battles is happening in Austin, Texas, where both Uber and Lyft threatened to leave after the city council voted to require fingerprint checks. Uber then supported a successful campaign to put the issue before voters this May, while signatures to recall a city councilwoman who pushed for fingerprint checks have been submitted to the city clerk. Both Uber and Lyft have said they do not support the recall effort.

In California, two efforts in the state Legislature by Assemblyman Adrin Nazarian (D-Sherman Oaks) that would have required fingerprint checks died in committee. However, Assemblyman Jim Cooper hopes a bill he introduced in September requiring stricter background checks will pass this time around.

"I scratch my head when I hear that Uber drivers in New York are fingerprinted," said Cooper, a former sheriff's captain. "Whatever Uber's background check is, it should be consistent. And right now, in talking to other jurisdictions, it's inconsistent."

Cooper, whose daughter is an Uber driver, said he believes the CPUC hasn't required tougher background checks because it lacks resources and is "spread very thin."

Though he agrees fingerprint checks are the gold standard, his bill doesn't explicitly require fingerprint checks because the Elk Grove Democrat said he wants to first have a dialogue with the companies. For now, his bill calls for "comprehensive criminal background checks."

"Their current reporting standard is subpar at best," said Cooper, whose bill is expected to get its first committee hearing in the Senate later this year.

Sutton said ride-service companies may likely change their policies on background checks when enough customers demand it.