Cyr, 34, is on trial for second-degree murder. Shingoose was found lifeless, dead from blunt force injuries, in her bedroom June 21, 2012 by her mother Amanda Trevors. Cyr and Trevors were living together at the time.
"Did you cause those injuries?" Cyr's lawyer Bob Hrycan asked his client as he showed pictures of the dead girl.
"No I did not," Cyr responded.
Hrycan posed a similar, direct, question to Cyr about the child's death.
"Did you kill Natalia Shingoose?" he asked, and again Cyr replied, "No I did not."
Previous evidence provided in the case outlined how Shingoose suffered a loss of blood flow to the brain, multiple bone fractures and damage to her heart and liver due to some blunt force. The jury was told she died from either brain damage or cardiac arrest within four hours of being hurt.
Cyr had been babysitting the child while Trevors was at work. She has testified that she came home around 9 p.m., looked in on her daughter and saw Shingoose on her bed.
According to Cyr's testimony Wednesday, he spent about six hours alone with the child through the afternoon and evening of June 20, 2012. Cyr and Trevors had been living together since late 2011 and he often babysat Natalia, spending time with her watching TV or dancing.
He also testified that the child's mother would sell drugs from the home, including cocaine, to friends and other users.
"Obviously, [that's] not a good thing and I didn't care for it much, but it was her house," Cyr said.
'Natalia might have fell,' Cyr testifies
Cyr also told the jury about an event he recalled from the night before Shingoose was found dead.
He said he remembers he was in the bathroom and heard a loud bang in the house. When he went to check, he said the child told him she was OK.
Cyr testified that he believes he told Trevors about that when she came home.
"I told her I think Natalia might have fell," he said. He said Trevors looked at the child, in her bed, and told him the girl was fine.
Cyr also testified about a disturbance in the home, later in the night around 3 a.m., that woke him up. He said Matthew Bennett, a close friend who was a frequent visitor to the home, was in the house and yelling that the front door was wide open.
Cyr was also asked about what happened in the morning when Shingoose was found. Trevors has testified that she was frantic about finding Shingoose's cold body and called 911, desperately looking for help.
"Somebody had to help my baby," she testified earlier in the trial. "Somebody had to help her be OK."
Cyr, on Wednesday, claimed Trevors was acting calmly before calling 911 and told him to hide some marijuana that was in the house, along with a bong.
The trial continues.