New Haven, Connecticut (CNN) -- Steven Hayes, convicted of killing three members of a Connecticut family, has shown "suicidal tendencies" and expressed concern his food was tainted, a psychiatrist testified during the penalty phase of Hayes' trial Monday.
Dr. Justin Schechter, a Stamford, Connecticut, forensic and clinical psychiatrist, said that Hayes exhibited signs of depression after his 2007 arrest, but told him, "I would rather they kill me" -- reflecting Hayes' apparent hope that he'd be executed for his role in in the deaths of Jennifer Hawke-Petit and her daughters, 17-year-old Hayley Petit and 11-year-old Michaela Petit.
The jury must decide whether to sentence Hayes to death.
Hayes wasn't in solitary confinement or considered "actively suicidal," said Schechter, though there were concerns he had a seizure disorder, depression and anxiety. The high school dropout said he had a long history of substance abuse and had fathered two children out of wedlock, Schechter said.
Hayes believed that a doctor was "manipulating" his food and wouldn't eat it, said Schechter, though he did eat food from the prison commissary.
The court session ended with Schechter's testimony on Monday afternoon, and will resume Tuesday.
Hayes, 47, was convicted this month of 16 of the 17 charges against him -- including nine counts of murder and capital murder and four counts of kidnapping -- in the deaths of Hawke-Petit and her daughters.
Prosecutors allege that Hayes and Joshua Komisarjevsky invaded the Petit home in Cheshire, beat Jennifer Hawke-Petit's husband bloody, strangled Hawke-Petit, set the house afire and tried to flee. Komisarjevsky is to be tried separately.
Earlier in the day, Fred Levesque, former director of offender classification and population management for the state Department of Correction, testified that Hayes was written up for 24 disciplinary reports during a stretch in state prison. One of those was for hoarding medication, a charge to which Hayes voluntarily pleaded guilty.
Asked by the defense if he had any knowledge of whether Hayes was a threat to the general population, Levesque answered "no."
Last week, a forensic psychiatrist testified that Hayes attempted suicide several times since his arrest and has said he wants to receive the death penalty.
On cross-examination, Dr. Paul Amble said his panel did not address the question of whether Hayes' suicide attempts were sincere. But in his opinion, he said, Hayes was "making decisions that were rational, given his situation" when he said he wanted to receive the death penalty.
"I want to plead guilty to everything now, because I just want it over now," Hayes told an evaluation team, said Amble, the assistant clinical professor of psychiatry at Yale University School of Medicine.
Hayes described a plan to "look like a monster" to the jury, expressing no remorse, in an attempt to move the jurors to sentence him to death, Amble wrote in his evaluation of the defendant.
Prosecutor Michael Dearington asked Amble whether Hayes truly wanted to be executed. "I don't know," the doctor said. "I'm not here to say I can exactly divine his thoughts, only what he said."
In March, Hayes told a psychologist that he no longer wanted to commit suicide "but intended to let the state do it," said Amble, who had been asked by the judge in the case to determine whether Hayes was competent to stand trial.
Police testified that in the 2007 home invasion, Hayes and Komisarjevsky found evidence of a bank account containing $20,000 to $30,000 and forced Hawke-Petit to go to a bank in the morning and withdraw money from the account. Prosecutors said Hayes took her to the bank while Komisarjevsky stayed behind.
When Hayes and Hawke-Petit returned with the money, officials said, the two men set the home afire and fled. Inside the home, authorities said, Hawke-Petit, 48, was found raped and strangled. Her two daughters, one of whom had been sexually assaulted, died of smoke inhalation. Petit, the sole survivor, escaped to a neighbor's home.
CNN'S Brian Vitagliano contributed to this report.