The bill, which cleared the House and Senate recently with significant bipartisan support, would adjust juvenile justice reforms from recent years involving 16- and 17-year-old defendants.
The Democratic governor agreed with critics of the law who warned the changes were rolling back those "Raise the Age" provisions that originally took effect in late 2019 and ended a mandate that children of these ages be tried in the adult criminal justice system.
The removal of automatic prosecution in adult court was seen as a way to help more young people avoid public, lifetime criminal records for one-time mistakes while giving them access to youth-centered resources within the juvenile system, where records aren't public.
While senators worked to make the vetoed legislation better than the original bill, Cooper wrote in his veto message, "I remain concerned that this new law would keep some children from getting treatment they need while making communities less safe."
The bill's chief advocate in the General Assembly said the changes were sought to reflect the reality that these young people charged with high-level felonies were ultimately winding up in adult court, and the legal actions to move them from juvenile to adult court were clogging up prosecutors' juvenile caseloads. Sen. Danny Britt, who shepherded the bill, didn't immediately respond Friday to a text message seeking comment.
The bill now returns to the General Assembly for a possible veto override. Eighteen House and Senate Democrats combined voted for the measure, while one Republican voted no. Republicans already hold narrow veto-proof majorities at the General Assembly, which overrode all 19 of Cooper's vetoes last year. Another Cooper veto earlier this year has not been acted upon.
Juvenile justice law says cases of 16- and 17-year-olds accused of the most serious felonies must be transferred to adult court after a notice of an indictment is handed up, or when a hearing determines there is probable cause a crime was committed. Prosecutors have had discretion not to try these youths accused of lower-grade felonies in adult court.
The new language would have ended the transfer requirement for most of these high-grade felonies and simply place the cases of these youths in adult court right away.
North Carolina had been the last state in which 16- and 17-year-olds were automatically prosecuted as adults when "Raise the Age" was implemented. These youths are still being tried in adult court for motor vehicle-related crimes.
"Most violent crimes, even when committed by teenagers, should be handled in adult court. However, there are cases where sentences would be more effective and appropriate to the severity of the crime for teenagers if they were handled in juvenile court, making communities safer," Cooper's message read. "This bill makes this important option highly unlikely."
The bill also would have created a new process whereby a case can be removed from Superior Court to juvenile court - with the adult records deleted - if the prosecutor and the defendant's attorney agree to do so.
Children ages 13 through 15 who are accused of first-degree murder still must be automatically transferred to adult court upon an indictment or hearing that finds probable cause.
The legislation also would have raised penalties against adults who solicit a minor to commit a crime.
The Associated Press contributed to this report.