On Monday, Crown prosecutor David Scully summed up his case to jurors during the fourth week of the NSW District Court trial in Wollongong.

De Belin, 29, and co-accused Callan Sinclair, 23, are accused of jointly raping a then 19-year-old woman in a North Wollongong townhouse in December 2018 following a night out at Mr Crown nightclub.

The pair have pleaded not guilty to five counts of aggravated sexual assault and claim the threesome was consensual.

Mr Scully started by arguing the woman was a "compelling" witness and urged the jury to accept, beyond reasonable doubt, her evidence of what took place in the bedroom on December 9, 2018.

"On her version of events, the Crown argues, the sexual penetrations were not consensual and the accused would well have known those sexual penetrations were not consensual," Mr Scully said.

The prosecutor said the woman's evidence and version of events had been tested again and again, and he asked the jury to find her version, "credible and reliable".

The prosecutor said the defence may argue that the woman's behaviour at Mr Crown somehow indicated that she did later consent to sexual intercourse.

"The Crown submits that nothing about how the complainant behaved at that nightclub, in any way tells you she consented to being sexually penetrated by either or both of the accused in that unit," Mr Scully said.

"The complainant is a 19-year-old woman at Christmas time.

"She is allowed to get dressed up, she is allowed to go out, she is allowed to have a good dance and she is even allowed to have a fun kiss with Mr Sinclair if that's what she wants to do.

"None of that, the Crown submits, provides a foundation for an argument that because of what she was doing there, that she must have consented to sexual intercourse with the two accused back at the unit."

Mr Scully said the woman was never told the men planned to have sex with her and her intention was always to go to Fever Nightclub.

"The Crown argues the complainant never wanted to have sex with either Mr de Belin or Mr Sinclair," Mr Scully said.

"The two accused on the other hand had different ideas. They thought she was keen from her hanging around. They wanted to have a threesome with her.

"The fundamental disconnect is that neither of the accused, the Crown argues, bothered to tell the complainant about their plan to have consensual sex with her.

"Neither of the accused bothered to tell the complainant they wanted to go back to the unit much less that they wanted to go back to the unit because they wanted to have sexual intercourse with her."

Mr Scully said the Crown did not suggest the pair planned to sexually assault the woman prior to going to the unit but they hoped or expected once they got her there that sex would naturally follow.

He said it was not unsurprising that the woman did not remember every moment or movement on the dance floor because she was "not a robot" nor had a "photographic or video memory".

Mr Scully said the woman's inability to recall every moment was not her trying to hide anything from the jury, and was consistent with other witnesses' memory, including Sinclair not remembering the 'v' gesture made on the dance floor until he was shown it on the CCTV footage.

Mr Scully said the woman trusted Sinclair, Matthew Clune and Jai Field when they went to the taxi rank after leaving Mr Crown because they were all friends.

The prosecutor also backed up the claim the woman thought she was going to Fever Nightclub rather than back to the apartment as she sent a message to a friend saying "I'm going to Fever".

The jury's attention was also drawn to the vague direction de Belin gave the tuk-tuk driver Gary Poort. He told him, "you'll just have to trust me".

"He gave the driver a deliberately vague direction ... because he didn't want the complainant to know where they were going because it was never discussed with the complainant," Mr Scully said.

The prosecutor said the defence team would likely claim the woman sent a message to a friend, saying "want to get high?" while in the tuk-tuk because she wanted to smoke cannabis after having sex with de Belin and Sinclair.

However, Mr Scully said the message was irrelevant because she did not end up going to her friend's house to smoke cannabis but rather went home and "cried herself to sleep".

Mr Scully also told the jury that when they assessed the evidence presented to court, they should consider what was a "red herring" or a "distraction".

He submitted the evidence about Detective Senior Constable Shawn Adams lying under oath about viewing privileged information between de Belin and his lawyers was not relevant because the information obtained was never discussed with the woman.

Mr Scully went on to say the woman's actions after the alleged assault and the following day were consistent with her evidence and claims about what had occurred in the unit.

He urged the jury to consider the reasons why the woman ordered an Uber that took the trio back into the city, before they walked to the queue at Fever Nightclub.

"This event had occurred and the complainant was very upset and they (de Belin and Sinclair) didn't want it to end that way; they wanted her to be with them in public so it would be all normal again," Mr Scully said.

"You can also well understand, from the complainant's point of view why she agreed to go with them....she is alone with two men and and event has occurred which involved a significant violation and a significant power imbalance.

"She is in a very, very, very vulnerable position. She is a 19-year-old and is still in a state of shock and is still trying to process what has occurred."

Mr Scully also said the woman was "trying to put on a brave face" when fans asked for a photo with de Belin outside Spotlight on the way to Fever, and that explained why she could be seen laughing on CCTV footage when walking to the queue.

"She can be seen laughing for a brief moment in time but if you look at how the accused and the woman are walking prior, she is not smiling or laughing," Mr Scully said.

The prosecutor said the woman's messages to friends were "cries for help" when she sent, "help", "nah I'm not ok" and "those guys you saw me with just f**king abused me sexually" only minutes after leaving the queue.

He said the messages supported her evidence that she had been sexually assaulted.

Mr Scully finished the day by drawing the jury's attention to the evidence provided by the woman's managers and work colleague. The court previously heard the woman told them various information about the alleged assault on Sunday, December 9.

The prosecutor said their evidence, while they had slight inconsistencies which were to be expected, overall supported the woman's claims.

The trial continues.