Paragraph 11 reads: "Part of Chappell's defense on the child abuse incident was "involuntary intoxication" from Wellbutrin, an anti-depressant, but prosecutor Frankie Grimsman said there is no evidence that the drug causes anger."

http://www.azcentral.com/news/articles/0828mesaverdict0828-on.html

Man found guilty of first-degree murder in drowning of tot
Jim Walsh and Michael Kiefer
Aug. 28, 2007 02:24 PM

Jurors took only a couple of hours to find a 25-year-old Mesa man guilty today of first-degree murder in the drowning death of his girlfriend's two-year-old son at an apartment complex.

The speedy verdict moves Derek Chappell a step closer to a possible death sentence the slaying to Devon Hinman Shackleford on March 11, 2004, at an apartment complex near Dobson and Guadalupe roads.

"Early that morning, when he walked Devon to his death, he silenced him forever," Deputy Maricopa County Attorney Patricia Stevens said during closing arguments Monday before Superior Court Judge Robert Gottsfield in Phoenix.

"He put him in the water and held him down while the child struggled for life," she said. "He walked away from the child and left him facedown floating in that pool."

Jurors also found Chappell guilty in a child abuse incident four months earlier when he was accused of choking Devon.

But Lawrence Matthew, Chappell's defense attorney, disputed the prosecution's theory that Chappell killed the boy because his Devon's mother, Kristal Shackleford, also 25, picked the child over the defendant a day before the slaying.

Chappell had been accused of choking Devon in a December 2003 incident and state Child Protective Services had warned her to discontinue her relationship with him. The couple broke up, but Stevens said they secretly resumed their relationship.

"He had no need to kill Devon because he already was with her," Matthew said, noting that the two were engaged to marry on March 6. "There was no reason for Derek to do anything except shopping for a bigger ring, because that's what Kristal wanted."

He said all Chappell had to do to settle the CPS issue was to send a letter to the agency, saying "he was stabilized" by mental health treatment.

Stevens said the child abuse incident left broken blood vessels on Devon's neck, while Matthew said it was an accident while Chappell attempted to change Devon's diaper.

Part of Chappell's defense on the child abuse incident was "involuntary intoxication" from Wellbutrin, an anti-depressant, but prosecutor Frankie Grimsman said there is no evidence that the drug causes anger.

Matthew also suggested that Shackleford could have been responsible for her own son's death. Immediately after his arrest, Chappell said she had planned the murder, an allegation she denied. Shackleford never was charged with any crimes.

Matthew noted how a Mesa fire captain was shocked by her reaction to her son's death.

"The mother's demeanor is emotionless, subdued," he said, quoting the testimony of Capt. Dan Broadley. Her reaction seemed "disingenuous."

But Grimsman said Shackleford's reaction may have been "a woman wracked with guilt" from poor decisions.