Morgan Lane Arnold

Morgan Lane Arnold has been charged as an adult with first-degree murder and other counts in the stabbing death of her father, Howard County blogger Dennis Lane. (Photo provided by Howard County Police Department / May 13, 2013)

An attorney for a Howard County teenager accused of conspiring to kill her father said in court Wednesday that the girl was manipulated by her older boyfriend and that it would be unjust to try her as an adult.

Prosecutors, though, say lawyers for 16-year-old Morgan Lane Arnold have put on a performance for the court, placing stuffed animals on the defense table as props to make the girl appear more childlike than she is.

"It's a show," said prosecutor Danielle Duclaux.

Arnold is currently charged as an adult with first-degree murder in the May 2013 death of her father, businessman and community blogger Dennis Lane, who lived in Ellicott City.

Howard County Circuit Judge William Tucker said he will rule Monday whether Arnold's case should be sent to juvenile court. Wednesday was the third day of testimony in the hearing after two sessions last week.

Arnold's then-boyfriend, Jason Bulmer, pleaded guilty in February to stabbing Lane to death. Both prosecutors and defense attorneys for 20-year-old Bulmer, who was sentenced last month to 30 years in prison, contend that Arnold asked Bulmer to kill her father.

But Arnold's defense attorney, Joseph Murtha, said it was Bulmer's idea.

"Morgan Arnold is mentally ill, influenced by an older individual who I believe manipulated her and took advantage of her," Murtha said.

The couple had also planned to kill Lane's girlfriend, Denise Geiger, according to evidence presented in court.

Throughout court proceedings, Arnold read books and appeared to not pay attention. Stuffed animals sat on the table in front of her and on a chair behind her.

Duclaux said Wednesday it was all a ploy. She said Arnold thrived on violent fantasy and used Bulmer to get what she wanted. She read a series of electronic messages between the two in which they discussed killing Lane, their wish to poison a school counselor at Mount Hebron High, which they both attended, and Arnold's desire to kill her mother as well.

Much of the testimony Wednesday focused on Arnold's relationship with her mother, Cindi Arnold. The prosecution played recordings of the girl's conversations with her while the teen was in jail. In the calls, the mother and daughter both spoke disparagingly of Geiger.

"They're laughing — laughing," Duclaux said. "It's chilling. It's mind-boggling that this is the relationship between Cindi Arnold and her daughter."

Arnold said in an interview after the hearing that the recordings did not accurately depict the context of her communications with her daughter.

"I think it's really sad that the prosecution picked mere moments out of hundreds and hundreds of hours out of communications, took them out of context and tried to make me look like the bad mom, as though that were the crime being charged," she said.

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