AUGUSTA – In a ceremony that stemmed from tragedy, Gov. John Baldacci joined the family of a teenage manslaughter victim Tuesday in marking passage of a bill to allow blended adult and juvenile sentences in certain cases.

The bill became known as “Marlee’s Law” in memory of Marlee Johnston, who was 14 when she was killed by a teenage neighbor in 2005.

Patrick Armstrong, a neighbor in Fayette who was also 14 at the time of the killing, pleaded guilty to manslaughter in December 2006 in juvenile court and was ordered to serve nine years in prison, followed by four years of probation.

The case prompted Ted Johnston, the victim’s father, to advocate legislation allowing combined or blended sentences for the youngest offenders.

Due to special circumstances in Armstrong’s case, he could be given a mixed juvenile-adult sentence. His pleas on unrelated burglary charges enabled authorities to send him to juvenile detention, while charging him as an adult for the more serious crime.

But if that had not been the situation, prosecutors would have had to choose between trying Armstrong as an adult and sending him to an adult prison, or trying him in juvenile court where the maximum penalty is incarceration until age 21.

Armstrong has been confined since his conviction to the state juvenile facility in Charleston. His transfer to the state prison will come between ages 18 and 21.

The bill Baldacci ceremonially signed Tuesday allows a more general application of blended sentences in which prison time can be split between a juvenile and an adult facility. The governor actually signed the bill April 24.

Johnston said he advocated for the sentencing policy to honor his daughter’s kind and compassionate nature.

Baldacci commended Johnston and his wife for recognizing that the person who took their daughter’s life was a juvenile and should be treated as such.

“We all hope that tragedies like the loss of a young person, like Marlee Johnston, won’t occur again in Maine,” Baldacci said in a statement. “This law, Marlee’s law, will ensure that if such a tragedy does occur, the perpetrator will serve a sentence that befits the crime in an age-appropriate facility.”

The bill allows prosecutors, in the most egregious cases, to charge juveniles as an adult.

“The juvenile will serve the initial portion of their sentence in a juvenile facility and then they will finish the remainder of their sentence in an adult facility,” Baldacci said.