The 15-year-old from Kingsville is accused of bringing his father's shotgun into the cafeteria and shooting fellow student Daniel Borowy on the first day of school. Gladden has been charged as an adult on 29 counts, including attempted first-degree murder. If tried as a juvenile, the longest he could be held is until his 21st birthday.
"This is not Columbine. This is not Newtown. This is a young man who made a horrible mistake," said Gladden's lawyer, George Psoras Jr. "Mr. Gladden deserves a chance."
During his opening statement, Psoras said it would be "a real tragedy" to charge Gladden as an adult, saying the teen's life would be thrown away and he would suffer at an adult institution, where he would be preyed upon by older, larger offenders. He said Gladden was in need of intense psychiatric treatment.
While his defense attorney referred to his troubled childhood, prosecutors pointed out Gladden's threatening, sometimes violent behavior.
Assistant State's Attorney John Cox referred to reports from staff at Spring Grove Hospital, where Gladden was evaluated after his arrest, that he initiated fistfights with a 12-year-old in the boys bathroom, cracked his knuckles while standing over a group leader in an attempt to intimidate and, along with a peer, made persistent threats to a patient, who had to be placed in protection.
Several witnesses, including a social worker and mental health professionals who evaluated Gladden, said that from a very young age he struggled in school because of a lack of motivation. Gladden, who was being treated for attention-deficit hyperactivity disorder in middle school, was suspended numerous times, including once when he brought oregano to school, pretending it was marijuana. Another time, he wrote threatening exchanges to a student on Facebook, leading to a suspension in ninth grade.
Gladden had no prior juvenile record.
Cox played a recorded call from jail in December between Gladden and a cousin, in which Gladden said, "You know what school I wish I went to? Sandy Hook Elementary." Sandy Hook Elementary in Newtown, Conn., was the site of a shooting in December that left 26 students and staff members dead.
Dr. Aaron Noonberg, a clinical psychiatrist who evaluated Gladden's behavior, said he did not interpret the comment as a threat but believed it mirrored Gladden's past behavior in making comments to get a rise out of others.
"He needs in-patient treatment for quite a long time," Noonberg said, but added that he was optimistic that Gladden has responded to a few months' treatment while at the county detention center, where he has seen a therapist and is being given Prozac for depression.
Although Gladden and his parents said the family "had a fairly good relationship," there had been trouble, said Dani Davis, a social worker for the Department of Juvenile Services, who evaluated Gladden after the shooting.
After his parents' divorce, Davis said, Gladden's relationship with his mother turned rocky and his father became more removed from his life. The family told her, however, that their relationships were on the mend. She said Gladden told her he dyed his hair black to look more like his father.
She said Gladden also faced difficulties in his education, developing early on "an extreme hatred for school." He did poorly until entering an alternative school, where he attended eighth grade. His academic improvement led school officials to recommend that he return to mainstream education, and he completed his freshman year at Perry Hall.
Gladden's performance again deteriorated, and he received poor grades and faced several suspensions.
The hearing will continue Thursday. His trial is scheduled for Feb. 19.