Two months after Baker's body was found tied up in his home, Fatu gave a police interview which was played to the jury today.
"Tell me about your knowledge and involvement into the death of Shannon Baker," detective Oliver Chen asked.
Fatu said he had been drinking and smoking on the night in question.
He claimed that when he walked into the Calgary St flat it was already too late.
But he also said he knew he "could have stopped whatever happened" and he was sorry.
Chen said it sounded like it had been "eating away" at Fatu's conscience.
As the interview progressed, the detective questioned whether Fatu was giving him the full account of what transpired.
"You know what actually happened that evening and you're trying to minimise your involvement," Chen said.
"Now tell me what really went on."
Fatu again claimed he thought they were just going to meet up to smoke.
However, he then said they had planned to rob the house for drugs and once inside the flat they took turns holding Baker down.
Fatu also admitted he had a hammer with him because he was worried there might be a weapon at the address.
"I had a hammer with me but we didn't use it."
He claimed he did not have any involvement in gagging Baker and that he left the flat shortly before Ekeroma.
"I wasn't there when that happened," he said.
He also claimed he had told Ekeroma that they should leave.
"I should have untied him [Baker]. But everything happened so fast ... I was just trying to get out of there.
"I didn't think that he was going to die or anything."
Fatu later said in the interview that "everything went wrong".
"I went in there and I backed him up because I didn't want anything bad to happen to him, to Don either.
"That's just the kind of person I am.
"I didn't want anything bad to happen to him and I didn't want anything bad to happen to anybody."
Justice Jagose has directed the jury that they are only to use the police interview as evidence in respect to Fatu.
The interview is inadmissible in respect to Ekeroma.
At the beginning of the trial, Crown prosecutor Brett Tantrum told the jury the 55-year-old Baker was the victim of "a severe beating" during a gruesome home invasion.
Baker's cause of death was asphyxiation but strangulation could not be ruled out, Tantrum said.
The victim had consumed some methamphetamine but this did not contribute to his death, Tantrum said.
The trial is expected to take two weeks.