The jury in the Mariora Rostas murder trial has heard that key prosecution witness Fergus O'Hanlon was never promised any benefits while in the witness protection programme.
The trial also heard that original notes of meetings between witness protection gardaí and Mr O'Hanlon were destroyed.
A garda sergeant involved in the witness protection programme said Mr O'Hanlon would have been informed that he would be provided with social housing and social welfare once he exited the programme.
He told the court: "It's a like for like situation. He was unemployed before so he would be returned to social welfare and given training.
"He would be returned to social housing. It was never about getting anything from us, it was not about promises," the garda said.
Asked by defence counsel Michael O'Higgins why original notes were shredded, the garda said key words would be written down during the meeting and a full note would be written up later.
The garda said he was not aware of any other department in An Garda Síochána where there was a policy of destroying original notes.
Mr O'Higgins said he would like to see the note of where Mr O'Hanlon had been "seized with altruism" or wanting to do the right thing.
He also asked the witness if Mr O'Hanlon had ever threatened to give his name to other criminals.
The witness said he had not but he was aware Mr O'Hanlon had said this to other witness protection gardaí.
Alan Wilson of New Street Gardens in the city has pleaded not guilty to murdering Ms Rostas at Brabazon Street, The Coombe between 7-8 January 2008.
Ms Rostas went missing on 6 January 2008 while begging in Dublin city centre. She had been in Ireland for 18 days.
The 18-year-old girl died from gunshot wounds to her head.
Her body was buried in a shallow grave in the Dublin Wicklow Mountains where it was discovered four years later.
A solicitor who previously acted for a key witness in the trial said notes of a meeting with gardaí in which immunity from prosecution was mentioned were accurate.
Bridget Rouse, who previously represented Mr O'Hanlon, confirmed that her notes recorded that Mr O'Hanlon had asked about immunity from prosecution in return for a statement and for showing gardaí where the girl's body was buried.
The notes also record that gardaí said immunity was an issue that could only be decided by the Director of Public Prosecutions.
Investigating gardaí have denied that Mr O'Hanlon ever asked for immunity in exchange for information about the disappearance of the teenager or that the issue of immunity was ever discussed before he gave the information.
A garda witness told the trial today that the solicitor's note about immunity was "nonsense".
Ms Rouse also said she advised Mr O'Hanlon that he could be charged after making a statement to gardaí about the girl's disappearance and that, notwithstanding this advice, he still wanted to co-operate.
The evidence has now finished in the case which is in its closing stages.
The case will be in legal argument tomorrow and the jury returns on Monday.