Story highlights Marlon Brown died on May 8 after he was run over by a DeLand, Florida, police officer

The police officer was fired, but a grand jury decided not to indict him

Outraged, his family released dashcam video of his death

The family want the police officer to face criminal charges

The family of a Florida man has released video of his death, hoping to get criminal charges filed against the police officer who ran him over.

On May 8, Marlon Brown was being chased by DeLand police because they allegedly saw that he was not wearing a seatbelt. At a dead-end road, Brown stopped his car and started running.

One of the police cars hit and ran him over, its dashcam video recording the entire incident.

Last week, a grand jury decided not to indict officer James Harris on a criminal charge of vehicular manslaughter. That's when the family decided to go public, and release the video.

"We knew it wasn't going to be an easy video to watch," says Krystal Brown the ex-wife and mother of Brown's children, "but in order to obtain justice, and that's what we're looking for, we knew it was something that we had to do."

Justice, the family says, would be criminal charges against Harris for killing Marlon Brown. Harris, who has been fired as a result of the incident, could not be reached for comment.

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The dashcam video shows Harris' police car following two other police cars as they drive down a residential street into a grass lot. The two other vehicles stop but the one with the camera continues to chase after Brown.

As the police car approaches, Brown stumbles and falls. While on the ground, Brown turns and faces the chasing vehicle and within seconds, his face disappears under the hood of Harris' police car. A thud is heard and the car stops.

"I think he's underneath the (expletive) car," a voice off camera can be heard saying.

The city of DeLand has already paid the family $550,000 in a settlement but the city did not admit any wrongdoing, according to Krystal Brown. The family decided to go public with their story and the video in hopes of triggering public outrage that would result in pressure for officials to file criminal charges for Brown's death.

"We're just asking for justice, nothing extra," Krystal Brown said, "nothing no one else would want for their family member. "

State Attorney for Florida's 7th judicial district R.J. Larizza decided to present the evidence to the grand jury instead of filing charges, which he could have done if he felt a crime had been committed.

Larizza stood by his decision at a news conference last week, following the grand jury's decision not to return charges after two days of testimony.

"This has been a controversial situation and this has been a case that has been a challenge since the beginning," Larizza said at the news conference

"I wanted the most possible folks involved, people that were in the community, people that live here, people that care about this community to make the decision," said Larizza, adding, "and I was confident and comfortable that they would do so."

Krystal Brown said the family was "disappointed" and "felt let down by the criminal justice department" even before seeing the video, adding that they believe a vehicular manslaughter charge was appropriate.

"Just knowing what the charge entails, it doesn't have to show intent -- it only has to show reckless driving," she said.

The video alone prompted DeLand Police Chief William Ridgway to fire Harris.

"The actions taken by Officer Harris that night are not consistent with our department's training, directives, or accepted practices or techniques," Ridgway told CNN, in a prepared statement.

DeLand police are conducting an internal review of the incident. This week, law enforcement officials have been going over more than 2,000 documents to determine whether appropriate tactics were used, whether police policies were followed and if those policies reflect the best way to deal with similar situations.

Brown's family believes the video speaks for itself.

"We would have had no problem getting a call that morning saying, 'OK Marlon ran from the police and we had to tase him' or 'the dogs bit him' or something more along the lines of not using excessive force," says Krystal Brown. "But to get the call that he has been ran down with a vehicle for running from the police? That doesn't fit."