North Miami's chief of police has defended his members' practice of using the mug shots of black teenagers as target practice, saying the department's policies were "not violated".

Valerie Deant, a sergeant in the National Guard, was reduced to tears when she visited a Florida shooting range only to see her brother's image riddled with bullet holes.

Woody Deant was arrested in 2000 for drag racing at the age of 18 and was less than impressed with the use of his face for target practice.

"Now I'm being used as a target?" he told NBC Miami.

"I'm not even living that life according to how they portrayed me as. I'm a father. I'm a husband. I'm a career man. I work 9 to 5."

But police chief J. Scott Dennis said the practice is essential for "facial recognition" and insists the target was created at random.

On the target Sgt Deant saw, only mug shots of African-American men were being used.

Dennis did concede that the photographs should have been removed from the firing range after the training was finished.

Former FBI agent Alex Vasquez disagrees, however.

"The use of those targets doesn't seem correct. The police have different options for targets. I think the police have to be extra careful and sensitive to some issues that might be raised."

The Deant family is seeking legal advice.

Police chief says shooting at mug shots is essential for 'facial recognition'. (Supplied)