He is accused of raping his 18-year-old cellmate in Upper Hutt's Rimutaka Prison on multiple occasions, as well as forcing him to perform oral sex, every night from mid October 2017 to early January 2018.
He is also alleged to have threatened to kill the complainant if he reported the alleged offending or tried to move to a different cell, at one point pulling a shank on the man.
The complainant gave evidence in court on Monday, saying if he refused to engage in the sexual acts Goundar would slap and punch him repeatedly until he complied.
The alleged abuse ended when an anonymous tip-off was made, and Goundar was moved out of the unit. The complainant gave a statement to police later in the year.
In court today, the lawyers gave their closing addresses to the jury of eight men and four women.
Defence lawyer Karun Lakshman began his address with the demand: "show us the shank".
Corrections staff did not find a shank when they searched the cell, which Lakshman suggested was because the shank never existed.
"It exists only in the litany of lies that you've heard from [the complainant]."
He told the jury the complainant had lied throughout his evidence, and that his allegations had "gaping holes".
He pointed to the complainant's evidence that the first two nights in the cell Goundar asked for sexual favours and the complainant refused, and nothing happened.
The complainant later said under cross examination Goundar still hit him on the first two nights when he refused.
It was also important for the jury to remember Goundar's 2011 offending was against a female, and the complainant in this case was a male, Lakshman said.
"If Mr Goundar was the manipulative sexual predator the Crown says he is, then I suggest to you he had all the opportunity in the world to manifest that behaviour, manifest that tendency well before 2017."
He also noted three neighbouring inmates told police they had never seen or heard anything out of the ordinary between Goundar and complainant.
Crown prosecutor Jamie O'Sullivan said Goundar's previous offending was a strong indicator that showed his "modus operandi", and urged the jury to look at the similarities between the two cases.
"[The complainant] had no way to know the detail of Mr Goundar's previous offending, but the similarities are still there. "
Similarities included young complainants who were vulnerable and isolated - both by circumstance and then by Goundar - with Goundar presenting a friendly face to allegedly lure them away.
In the first case he then demanded oral sex, resorting to violence and death threats until he got his way.
"It's a case about power, domination, and control," she said.
The absence of a shank was not particularly relevant, because it could easily have been hidden, disassembled, or given to a friend for safekeeping, she said.
O'Sullivan also noted the three neighbouring inmates who spoke to police might have seen or heard things but chose not to tell police.
"Just think about the context, because you're talking to the police about another inmate while you're still inside."
Tomorrow morning Justice Karen Clark will summarise the case to the jury, and they will then be sent away to deliberate on the charges.
Where to get help:
• If it's an emergency and you feel that you or someone else is at risk, call 111.
• If you've ever experienced sexual assault or abuse and need to talk to someone call the confidential crisis helpline Safe to Talk on: 0800 044 334 or text 4334. (available 24/7)
• Male Survivors Aotearoa offers a range of confidential support at centres across New Zealand - find your closest one here.
• Mosaic - Tiaki Tangata: 0800 94 22 94 (available 11am - 8pm)
• If you have been abused, remember it's not your fault.
• Wellington HELP has a 24/7 helpline for people who need to speak to someone immediately. You can call 04 801 6655 and push 0 at the menu.
