By J.D. Miles

DALLAS (CBS 11 NEWS) – A Dallas police officer, with a history of trouble, is back on duty less than two weeks after killing a man during a struggle.

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The family of that man, 25-year-old Clinton Allen, doesn’t believe the shooting was justified and has filed a complaint against the officer.

Allen’s mother says the family was suspicious about the circumstances of the shooting and conducted an internet search of Dallas police officer Clark Staller.

Police say Allen was threatening his girlfriend at an apartment complex on the night of March 10, when he physically confronted Staller.

DPD released a statement saying the officer, “fearing for his life, fired his duty weapon.”

Allen died after being shot multiple times according to the medical examiner.

“I want to know what happened.  I want to know why my son isn’t here,” questions Allen’s mother, Collette Flanagan.

Allen’s mother visited DPD police headquarters this week to confront department officials, after she learned that Officer Staller was suspended for 20 days last year for lying after he denied running over a burglary suspect in his patrol car.

Staller reportedly told investigators after the incident, “I realize I screwed that up.”

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At the time, a high-ranking chief called his actions very disturbing.

Allen’s sister, Chaedria Labouvier questions why Allen is back on the street.

“This police officer has issues with telling the truth and i have a problem with that,” she said.

Allen’s family says although he had a criminal record, he did not deserve to die.

“We want to know what happened.  That’s our loved one. Clinton was my only son. I loved him. He had a family,” says Flanagan.

Police told Flanagan and her daughter they would have to wait until the outcome of administrative and criminal investigations.

DPD officials declined to comment on camera.

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