Prosecutors in Arizona on Friday moved to drop charges against the man accused in a string of freeway shootings that terrorized the Phoenix area last summer.
The move came after a judge on Tuesday reduced the bail of 21-year-old Leslie Allen Merritt Jr to nothing from US$150,000, clearing the way for his release later that day.
"We have a professional and ethical duty to act in the interest of justice and not merely seek a conviction and this is a textbook example of doing that," said Jerry Cobb, a spokesman for the Maricopa County Attorney's Office.
A ballistics expert has called into question the methodology used early on in the investigation that tied Merritt, a landscaper, to the shootings, Cobb said.
A judge is expected to rule to formally dismiss the case against Merritt as early as Monday.
Merritt was arrested last Sept. 18 and charged with 15 criminal counts, including drive-by-shooting and aggravated assault, for four of 11 shooting incidents along a stretch of Interstate 10 that passes through Phoenix.
The shootings, which occurred in late August and early September, struck fear among motorists in the area.