Chief Superintendent Andy Ward said: "This tragic event is the consequence of the activities of a small number of people who pick up weapons to settle their disputes.
"We've put enormous efforts into the area to target those involved in criminality.
"Through a combination of covert investigations and highly visible operations, we have reduced the number of shooting incidents.
"But despite repeated warnings that people continuing to use firearms on the streets of Merseyside would end up with loss of life, a small minority have chosen to continue."
Mr Smith, from Walton, was formally identified by his mother yesterday. He had three brothers and a sister.
He was walking across the car park when he was confronted by a hoodiewearing gunman in Brookfield Drive who shot him at close range.