SAN FRANCISCO — For more than a year, regulators in various cities have questioned whether Uber, the ride-hailing service, vets its drivers for criminal backgrounds as carefully as traditional taxi companies.
Now the district attorneys of San Francisco and Los Angeles have offered perhaps the most concrete evidence to date that people convicted of murder, sex offenses and various property crimes have driven for Uber, despite assurances from the company that it employs “industry-leading” screening.
The district attorneys said Wednesday that background checks used by Uber failed to uncover the criminal records of 25 drivers in the two cities. The charges were made in a 62-page amended complaint to a civil suit, originally filed in December, that claims Uber has continually misled consumers about the methods it uses to screen drivers.
“We are learning increasingly that a lot of the information that Uber has been presenting the consumer has been false and misleading,” said George Gascón, the district attorney in Uber’s hometown, San Francisco.
As Uber has aggressively pushed its service into cities around the world, often not waiting for permission from local regulators, it has faced hostility from local taxi drivers who fear it is undercutting their business, as well as increasing skepticism regarding the trustworthiness of some of its drivers.
Some of the most pointed questioning has come from Mr. Gascón, who argues that Uber’s background checks are not as thorough as another service, called Live Scan, that is typically used by taxi companies.
He said in a news conference Wednesday that about 30,000 registered sex offenders in California did not appear in a public registry Uber uses in its background checks. The checks also go back only seven years.
“So, for example, if someone was convicted of kidnapping eight years ago, and they were just paroled last week — they just got out of prison — the Uber background check process will not identify the person as a convicted kidnapper,” Mr. Gascón said.
He said this was “troubling and misleading to Uber customers and to the public at large” because Uber says its process goes back as far as the law allows.
Mr. Gascón was careful to couch this as a case of consumer deception. Uber is not by law required to use the Live Scan system favored by district attorneys. The question is whether the consumer is getting all the right information, he said.
The suit, which Mr. Gascón said “is only really scratching the surface,” does not name the criminals but includes some details about their crimes. One driver was convicted of second-degree murder in Los Angeles in 1982, and spent 26 years in prison before being paroled in 2008. He applied to be an Uber driver under a different name from those in his court records.
The complaint said Uber’s background check process could not identify the driver because it does not use biometric identifiers, like a fingerprint; because it cannot access criminal records that help to track aliases; and because the checks do not go back as far as the law allows. The complaint added that the Live Scan process would have identified the driver’s criminal past.
One driver was convicted of felony sexual exploitation of children in Wyoming in 2005, and another of “felony kidnapping for ransom with a firearm” in 1994. Other drivers were convicted of charges like robbery, assault with a firearm, identity theft and driving under the influence. Several were convicted of more minor charges, like welfare fraud.
“The main concern that we have here, and that we continue to have, is the fact that the consumer is not given the information, you know, the truthful information, in order to make an informed decision,” Mr. Gascón said.
The amended filing also asserts that Uber representatives continually changed their description of Uber’s screening.
An Uber representative said in a statement that the company’s background check method was no worse than Live Scan. “The reality is that neither is 100 percent foolproof — as we discovered last year when putting hundreds of people through our checks who identified themselves as taxi drivers,” the Uber statement said. “That process uncovered convictions for D.U.I., rape, attempted murder, child abuse and violence.”
In a recent blog post, the company also said that going back seven years in background checks was guided by two California laws that aimed to make it easier for criminals who have done their time to ease back into the work force by loosening the restrictions on what they have to disclose to prospective employers.
“We understand that there are strongly held views about the rehabilitation of offenders,” the post said. “But the California State Legislature decided — after a healthy debate — that seven years strikes the right balance between protecting the public while also giving ex-offenders the chance to work and rehabilitate themselves.”
Uber, which recently celebrated its fifth anniversary, is already valued around $50 billion by investors. The company has raised a multibillion-dollar war chest to finance a global expansion and move into areas like food delivery. But government officials say that in its pursuit of breakneck growth, the company is cutting corners on background checks.
The company and its competitors use background check companies that can turn around requests in a day or two. And in states across the country, Uber — along with its rivals Lyft and Sidecar — have repeatedly fought proposals that would require them to match the checks required of traditional taxi drivers.
In California, for instance, Uber and other companies successfully lobbied to kill a law that would have required drivers to undergo a background check by the state’s Justice Department, as is required of taxi drivers.
The suit by the Los Angeles and San Francisco district attorneys includes other charges like operating at airports without permission. Lyft, Uber’s largest American competitor, has already settled with the district attorneys for $500,000.
An earlier version of this article omitted an accent in the surname of the district attorney of San Francisco. He is George Gascón, not Gascon.