The UberX driver accused of striking a passenger in the head with a hammer during a ride in San Francisco did not have a previous criminal record — but that fact didn't stop SF's District Attorney from using the crime as a platform to repeat his concerns over the ridesharing company's background check practices.

As previously reported, 26-year-old Patrick Karajah, a driver for "the low-cost Uber" option, Uber X, picked up Roberto Chicas and a male and female friend from an SF bar at 2 a.m. last Tuesday.

After a disagreement with Chicas over Karajah's chosen route, the driver allegedly told everyone to get out at Ellsworth Street and Alemany Boulevard, near 280.

Karajah then allegedly struck Chicas in the head with a hammer, causing cranial fractures and trauma so severe that, ABC7 reports, Chicas might lose an eye.

At a very brief press conference Friday afternoon, District Attorney George Gascon said that Karajah did not have a past criminal record, but repeated that he remains "concerned about how thoroughly Uber in particular has been vetting its drivers," the SF Business Times reports.

That's one of the reasons, Gascon says, that his office sent letters to Uber, Lyft, and Sidecar promising injunctive relief and civil penalties if the companies did not change certain policies and practices "quickly." One of those changes demanded is that the companies "remove all statements from their mobile apps, websites and other publications that imply their background checks reveal drivers’ complete criminal history," calling such claims "patently untrue."

What is apparently true is that Uber missed the past record of driver Daveea Whitmire, who allegedly called a San Francisco passenger a "dirty Mexican faggot" by the driver, and then was struck several times when he tried to take a photo of the driver and his license plate.

Whitmire "has a criminal record, including felony and misdemeanor charges, and at least one felony conviction involving prison time," Pando Daily reported, all issues that Uber apparently failed to discover.

Though Karajah, the suspect in the most recent case, did not have a record, one of his neighbors tells ABC7 that the driver's Pacifica home has had police there more than once on disturbance calls, and that "there's been some stuff at that house, brothers fighting."

As of Thursday, Karajah has pled not guilty to charges of with assault with a deadly weapon and battery with serious bodily injury, and is free on $125,000 bail. A request made by SFist to SFPD for Karajah's booking photo was not responded to at publication time.

Regarding the alleged assault, Uber is now in damage control mode, blanketing media outlets with a prepared statement that reads "Safety is Uber's #1 priority. We take reports like this seriously and are treating the matter with the utmost urgency and care. It is also our policy to immediately suspend a driver’s account following any serious allegations, which we have done. We stand ready to assist authorities in any investigation."

Meanwhile, ridesharing companies have been told that they must respond to the letter sent to them by Gascon and his counterpart in LA by today or "prosecutors are prepared to file legal actions seeking injunctive relief and civil penalties," the Chron reports.

Previously: UberX Driver Accused Of Bashing Passenger In Head With Hammer During SF Ride
District Attorneys Call Uber, Lyft, And Sidecar 'A Continuing Threat To Consumers'