AURORA, Colo. (KDVR) — New video shows the lead-up to a deadly crash involving an Aurora police officer.

This video comes from the surveillance camera at a home that backs up to Chambers at Bates Road.

It shows the police car speeding by, without emergency lights, right before the impact. A 44-year-old man in a Toyota Corolla was killed, and the Aurora officer was hurt.

Investigators say the officer was responding to a report of a suspicious person and did not have his lights and sirens on because it was not an emergency call, according to Colorado State Patrol.

The Problem Solvers looked into police protocol to help understand just how fast that officer may have been going.

What does Aurora police policy say about lights, sirens?

The officer’s SUV and the car collided Saturday night on Chambers Road at East Bates. Police say the driver of the Toyota reportedly ran a stop sign.

The video shows a marked police cruiser, zooming across the frame in a 40 mph zone on northbound Chambers. The video captures the sound of impact.

It shows that Chambers was pretty busy at the time and the officer was driving without lights or sirens.

Minutes later, the video shows a massive response as fellow officers and emergency crews showed up to what would become a deadly crash investigation.

So why didn’t the officer didn’t initiate his lights or sirens?

According to Aurora Police Department policy, “Under normal, non-urgent operating conditions, including responding to routine calls for service, operators of police vehicles will adhere to all existing traffic laws, driving defensively and in a safe, careful and a prudent manner.”

There’s also language that state law suspends compliance with some traffic laws when officers respond to an emergency call, including permitting officers to exceed the lawful speed limits, so long as the member does not endanger life or property.

Just hours after the crash, police said during a news conference that the officer did not activate his emergency equipment because he was responding to a non-emergent call. Police said the other car, which is not seen in the video, did not stop at a stop sign before the collision.

Colorado State Patrol is investigating.