Former Gauteng Health MEC Qedani Mahlangu says she believes that the decision to cancel the Life Esidimeni contract was not wrong.
"What went wrong is the implementation or the execution of the project," she said on Wednesday.
Mahlangu was testifying during her second day at the Life Esidimeni arbitration hearing in Parktown, Johannesburg.
She told the hearing that she accepted that she had a political responsibility to protect the patients from harm.
She said she also accepted that the department's conduct was inconsistent with the Constitution and the law.
However, Mahlangu would not accept that the cost-cutting exercise her department undertook had resulted in the death of 143 mentally ill patients.
"I wouldn't know who died of what...in my documents we sent to the ombudsman we presented the case numbers which were opened [at] the police station."
She said the deaths were inconclusive.
Adila Hassim, the advocate for Section 27, also quizzed her about taking patients to Weskoppies and Sterkfontein psychiatric facilities.
Hassim said it would have would have cost "six times as much" to take care of patients, defeating the point of the cost-cutting exercise.
Mahlangu said the institutions are academic hospitals.
She added that it would cost more for the "quality care" that patients would receive at Weskoppies and Sterkfontein, as opposed to the NGOs.
She also told the hearing the reason she tendered her resignation in 2016 was because she wanted to take political responsibility.
"Families lost their loved ones... and this will forever linger in my mind," she said.
Asked if she wasn't aware of concerns raised by health professionals before terminating the Life Esidimeni contract, Mahlangu said she received a letter in June 2015, which raised concerns.
She said she asked the head of department to have a look at it and deal with the concerns which she said were urgent.
"At no stage was I made aware that the HOD has reported to the premier that there is anything he did not like... at no stage was I aware that the HOD was afraid of me."
She said she would have stopped the Life Esidimeni project if she had all the information.