New father Jamal Mahmoud, 21, was allegedly attacked by three fellow prisoners in a battle over illicit phones and a knife on G Wing of HMP Pentonville on October 18 last year.
Melissa Modeste, who spoke to her husband in the hours before the attack, told the Old Bailey Mr Mahmoud claimed he could “get let out” of his cell to settle a dispute with a rival faction.
Asked if she found this surprising, Ms Modeste said: “No, because I know what the guards are like there. They let people out, they do favours like bring stuff in.”
The trial has heard how Mr Mahmoud was allegedly killed by three fellow inmates in a battle to control the wing’s “lucrative” contraband route.
Robert Butler, 31, Basana Kimbembi, 35, and Joshua Ratner, 27, deny murder as well as wounding Mr Mahmoud’s associate Mohammed Ali, with intent to cause him grievous bodily harm.
The location of the victim’s cell on the fifth floor of G Wing occupied a prime position, giving him power over the influx of contraband, jurors have heard.
Before his death, he was said to be angry about other inmates bringing in parcels without “cutting him in” on the deal.
Questioning Ms Modeste, Michael Holland QC, defending Kimbembi, suggested: “As far as parcels were concerned, it was his operation. It was the fact they were bringing parcels in without his permission.”
Mr Mahmoud spoke with his wife for around an hour and a half the night before he died, on one of the 15 phone numbers she had for him, the trial heard.
Ms Modeste said: “He wasn’t the happiest. He was being very blunt and I kept asking what was wrong.
“He said he felt violated. He said they pulled a knife on him.”
Ms Modeste said she brought one of Mr Mahmoud’s friends in on a three-way call on the morning of his death to help “calm him down”.
She said: “Jamal was in his cell. He said he was going to get someone to unlock his cell. He was saying something along the lines of ‘I’m not going to let this slide’.
“I told him he shouldn’t do anything and made a threat to him, saying I would never speak to him again.”
Emerson Cole, a prison officer on G wing at the time, was warned by an inmate that knives were stashed in a cell the day before the killing.
Mr Cole, now a senior officer, said of the inmate: “He had a concerned look on his face. He said he’d never seen nothing like it before.
“He said: ‘If it don’t kill one of you,’ meaning officers, ‘then it’s going to kill one of us,’ meaning prisoners.”
The following morning, the cell was searched but no blades were found.
Following the attack, Pentonville officers “voted no confidence in the governor” Kevin Reilly, the court heard.
Questioning, Mr Holland said: “The concern was the inquiry would seek to lay blame.Prison staff were concerned management were not going to take responsibility. Staff had made complaints they were overwhelmed.
“Matters were made worse when two prisoners escaped just over a fortnight later – it was like something out of The Great Escape, wasn’t it?”
James Whitlock and Matthew Baker went on the run in November last year after breaking out of the Victorian prison by sawing through a metal bar, clambering over the roof and swinging round a CCTV pole on a bed sheet.
The trial continues.