SPOKANE, Wash. -

The Spokane Police Department has forwarded on the results of their investigation into the deadly shooting in late March of a car thief by Gail Gerlach to the Spokane County Prosecutor's Office.

Gerlach shot and killed Brendon Kaluza-Graham as he attempted to steal Gerlach's SUV from in front of his home on March 25. Gerlach's SUV had been sitting in front of his home when Kaluza-Graham got in, pulled away from Gerlach's home and began driving away. Gerlach fired a single shot at the SUV as it pulled away, hitting Kaluza-Graham in the back of the head.

The SUV crashed into a garage a few blocks away and Kaluza-Graham was declared dead on the scene by medical personnel.

While investigating Gerlach's use of deadly force against Kaluza-Graham, they have looked at whether or not a threat still existed when he fired his pistol at his SUV as it was being driven away.

"This is a more complicated investigation than some, as far as use of force, whether it was justified so at this point we are still compiling the rest of the investigation and will confer with the prosecutor and move from there as to whether or not submit charges," Spokane Police Lieutenant Mark Griffiths said on March 27.

When Kaluza-Graham was shot to death stealing Gerlach's SUV the incident polarized our community; people fed up with crime and repeat offenders felt he got what he deserved. His grandparents think the car owner's use of deadly force was murder.

"We feel like he was executed, that, no this incident should have not ended in the loss of his life. We won't have our grandson again," Ann Kaluza said.

Gerlach told investigators his Chevy Suburban was already backing out of the driveway when he confronted the car thief. Gerlach says that's when Kaluza-Graham raised his arm and was holding what Gerlach thought was a gun. While Kaluza-Graham was carrying a screwdriver in his pocket a police inventory shows a search of the SUV turned up no signs of a pistol.

"No gun was recovered from the vehicle," Griffiths said. "There were some keys, a couple of key rings, shaved keys, which are keys that can be used to start a vehicle."

So now prosecutors have to decide if Gerlach's use of force was justified. The fact that he shot at Kaluza-Graham as he was driving away, the fatal round passed through the rear window, presents a problem for Gerlach, according to defense attorney Chris Bugbee.

"The use of deadly force, if the other person turns out to not armed with a deadly weapon, is going to be looked at with great scrutiny by law enforcement," Bugbee said.

"It is just critical, it is a tremendous responsibility to have a concealed weapons permit or if you just have a gun in your house, you gotta know the laws of the State of Washington and when you can use it and when you can't," Brendon's grandfather Mike Kaluza said.

The submission of the investigation to the prosecutor comes as the lab work, including ballistics and toxicology reports, has been completed.

During their investigation, detectives applied for a search warrant to search for evidence of second degree murder, however, the police department has not said whether or not they forwarded the results of their investigation with a charging recommendation against Gerlach.

If prosecutors decide to charge Gerlach for shooting Kaluza-Graham they may include the lesser charge of manslaughter and let the jury decide which charge is the most appropriate.