"When there is mandatory detention of undocumented immigrants and children,that runs counter to our interpretation of the convention,"he said.
The committee said it was"concerned that detention continues to be mandatory for all unauthorised arrivals,including for children,"in the report compiled after hearing evidence from human rights groups as well as the Australian government.
"Detention should be only applied as a last resort,"the report said,only when"strictly necessary"in each individual case,and should be for as short a time as possible.
It said it was concerned at Australia's policy of transferring asylum seekers to processing centres in Papua New Guinea and Nauru,"despite reports on the harsh conditions prevailing in these centres,including … overcrowding,inadequate health care and even allegations of sexual abuse and ill-treatment".
The Committee was concerned"in particular[about] the policy of intercepting and turning back boats,without due consideration of[Australia's] obligations"under international law.
Anyone who arrives or attempts to arrive in Australia seeking asylum or protection should be guaranteed that their claims are thoroughly examined,and be able to challenge any adverse decision.
"[Australia] should continue and redouble its efforts"to find an alternative to closed immigration detention.
Mr Grossman said the committee was also concerned by the high proportion of indigenous people in jails,and the situation of women in detention facilities,particularly indigenous women.
The committee also welcomed the Royal Commission into child sexual abuse,however it said it was"concerned"as to"whether the outcome of its work will result in criminal investigations,prosecutions and compensation for victims".
It also:
- - criticised the treatment of inmates at Roebourne Regional Prison
- - recommended the Australian government consider abolishing the use of tasers
- - expressed its'concern'over Australia's counter-terrorism legislation,including the"broad"definition of a terrorist act,and the detention powers of ASIO.
Fairfax asked if an Australian government spokesperson was available to respond to the committee's report,but has not yet received a reply.
In its appearance before the committee earlier this month,Australia's delegation said it"takes its obligations under the Convention very seriously. Since ratifying the Convention in 1989,Australia has worked to ensure Australia's laws,policies and practices are consistent with our international obligations."
Australia's permanent representative to the UN John Quinn told the committee that the government had"striven to improve the design and procedures of its migration programmes to enhance fairness,accountability and integrity.
"A robust returns process for dealing with those found not to be in need of protection is fundamental to the integrity of status determination processes."