Mr Bowen was the only witness to appear at the last hearing of the Australian Human Rights Commission inquiry in Sydney on Tuesday.
The former Immigration Minister, who held the position for almost three years under the past Labor Government, told the Commission that he stood by offshore processing of asylum seekers.
“Difficult decisions are necessary including offshore resettlement,” he said.
Mr Bowen also highlighted his decision to stop detaining children on Christmas Island following a visit there in 2010.
“I did not think that it was a suitable place for the long term detention of children and families, hence the decision I made,” he said.
'I did not think that it was a suitable place for the long term detention of children and families'
He had similar thoughts on Manus Island, despite being responsible for the opening of both the Manus Island and Nauru centres.
“I had the view that it would take considerable work before it would be suitable for any children,” he said.
However Commission President Gillian Triggs said the number of children in detention rose to "unprecedented levels" under Mr Bowen’s leadership, hitting 1992 in July 2013.
In her opening statement, Dr Triggs said Mr Bowen was responsible for the reintroduction in August 2012 of offshore detention centres in Nauru and Papua New Guinea.
“This policy, which has bipartisan support, is the reason there is now currently 183 children detained in Nauru,” she said.
Mr Bowen’s evidence follows that given by current Immigration Minister Scott Morrison, as well as submissions detailing allegations of sexual, physical and verbal abuse of children in immigration detention centres.
The Commission's inquiry also coincides with the condemnation of the Australian Government’s asylum seeker policy by the incoming United Nations human rights chief, Zeid Ra'ad Al Hussein.
“Australia's policy of offshore processing for asylum seekers arriving by sea, and its interception and turning back of vessels, is leading to a chain of human rights violations, including arbitrary detention and possible torture following return to home countries,” he said.
Mr Morrison rejected the allegations of abuse and said Australia was willing to discuss the matters with the UN's refugee agency.
