Uber driver had a 4.73 star rating, on five point scale, before Kalamazoo shootings

Uber doesn't plan on making any changes to its background check system after a driver allegedly opened fire on eight people in Kalamazoo, Michigan, on Saturday.

Detectives believe that 45-year-old suspect Jason Dalton shot eight people, six of them fatally, in various locations around Kalamazoo, Michigan.

Dalton had no criminal history and passed Uber's background checks as a result. Before the shootings, Dalton's overall rating was "good," Uber's Chief Security Officer Joe Sullivan said in a conference call with reporters on Monday.

Passengers had given him an average of 4.73 stars out of five. Uber deactivates drives whose ratings drop below a certain threshold.

"There were no red flags if you will that we could anticipate something like this," Sullivan said. Uber has said it is "shocked and devastated" by the incident.

The day of the shooting, several of Dalton's passengers complained about his driving, including a passenger who did call 911. Since it was a complaint about bad driving, Uber's security team didn't suspend him from the platform immediately. The team only suspends drivers immediately if it is a report about violence, Sullivan explained.

Dalton became on Uber driver on January 25th and in the following weeks, had completed slightly over 100 rides, Sullivan said.