Garda Keith Harrison has told the Disclosures Tribunal that gardaí leaned on Tusla to intervene in his family life for malicious reasons.
Tusla's lawyer said the allegation was incorrect and did not stand up to scrutiny.
Gardaí also dispute the allegation.
The tribunal is investigating contacts between Tusla and An Garda Síochána about Gda Harrison.
Gda Harrison told the tribunal this morning that he was in no doubt that Tusla was manipulated.
He said it was no coincidence that shortly after his partner, Marissa Simms, withdrew a statement made against him, a social worker visited their home in February 2014.
He said it was unusual that there was a gap of three months between the complaint and the visit.
Gda Harrison said the social worker seemed confused as to why she was at their home on 19 February 2014 and apologised.
Tribunal Chairman Mr Justice Peter Charleton asked if Garda Harrison was saying that gardaí somehow manipulated a change of plan to organise a home visit and if that was for malicious reasons.
Garda Harrison agreed.
He also said his partner told him that the social worker, Donna McTeague, told her that Ms McTeague's superior had been in contact with Sgt Brigid McGowan from Letterkenny and he said there was a close relationship between them.
Ms Simms told the Tribunal that she does not recall talking about a connection.
Garda Harrison said he stood over his recollection of what he said Ms Simms had told him.
Ms McTeague disputes that she suggested a close relationship between a garda and her superior and she also disputes Garda Harrison's account of the home visit.
She says she was clear why she was at the house and that the couple accepted an incident had taken place.
Cross examining Garda Harrison for Tusla, Paul Anthony McDermott SC suggested Garda Harrison could have addressed his concerns with the agency for the cost of a stamp by writing to it directly.
He said tribunals can run into millions compared to a 72 cent stamp, as it cost back in 2014.
Garda Harrison said he could never have known he would be sitting at the tribunal talking about intimate details of his life.
Mr McDermott also said to Garda Harrison that he had made a series of incorrect allegations about Tusla which had not stood up to scrutiny.
Garda Harrison said his allegations were not made against Tusla rather it was contacts between gardaí and Tusla.
Mr McDermott also said that Garda Harrison had sought to portray Tusla's visit as an abuse of power.
Mr McDermott said the records showed Garda Harrison understood perfectly well what the concerns were and he successfully engaged with them.
Harrison denies he put pressure on partner
Garda Harrison has denied that he put pressure on his partner Marissa Simms to go along with the allegations against Tusla and the gardaí.
Garda Harrison said he did not co-ordinate his story with her and he said he could not as he did not know what was in her garda statement until December 2014.
Under cross examination by Mícheál O'Higgins for An Garda Síochána, Garda Harrison said it was absolutely not true that he had put pressure on Ms Simms.
Mr O'Higgins said he had put Ms Simms in an impossible situation and that she was now bound to a ridiculous story.
Mr O'Higgins also asked Garda Harrison if he was keen to hitch his wagon to the train of whistleblower Sgt Maurice McCabe. Garda Harrison said no.
Earlier, Garda Harrison told the Tribunal that the Garda Pulse system was like a social media site.
He was questioned about why he had checked on his partner Ms Simms 23 times between 2008 and April 2012.
In particular, he was asked why he had checked on her in 2008, three years before they rekindled an old college relationship.
Garda Harrison said it was a sense of curiosity. He said the practice was widespread in the gardaí at the time and "the pulse database was like a social media site".
He said that had changed by the time he returned to work in 2017 after nearly three years' sick leave.