HALIFAX -- The sister of former Somali child refugee Abdoul Abdi said Thursday she was feeling hopeful after a Federal Court heard her brother's emergency request to temporarily halt his deportation proceedings.

"He would not be in these circumstances if it wasn't for the government," Fatouma Abdi said outside court in Halifax. "I hope that they correct their mistake and that they don't go forward with the deportation."

Abdoul Abdi, who never got Canadian citizenship while growing up in foster care in Nova Scotia, was detained by the Canada Border Services Agency after serving nearly five years in prison for multiple offences, including aggravated assault.

Abdi's lawyer, Benjamin Perryman, said federal officials turned down the 24-year-old's request to press pause on a deportation hearing while he pursues a constitutional challenge.

Abdi then asked the Federal Court to temporarily halt the deportation hearing -- scheduled for March 7 -- and Perryman made arguments on his behalf on Thursday.

The former refugee was not in court because he had to work -- one of the conditions of his release to a Toronto-area halfway house.

Justice Keith Boswell reserved his decision, but said he would likely rule before the hearing next month.

Perryman argued that going ahead with a deportation hearing while Abdi's constitutional challenge is ongoing will cause irreparable harm.

He said the Immigration Division hearing will inevitably lead to a deportation order given the circumstances of Abdi's case. He said the independent division can only look at criminal records and citizenship status -- Abdi was convicted of crimes and isn't a Canadian citizen -- and cannot look at other possible factors in his case, including international human rights law and the Charter.

"What we're asking for is some analysis, some consideration of the issues, particularly in the context of a child who grew up in the care of the state and was effectively denied citizenship by the failures of multiple governments in the country," said Perryman.

"If the deportation hearing proceeds, there will be no consideration of the merits of his case. He has to automatically lose his right to work and his right to health care at this key time in his rehabilitation efforts in Canada.

"If he cannot work, he cannot meet the conditions of his release... He may be at risk of suspension and returning to jail."

Heidi Collicutt, a lawyer for the federal government, argued that Abdi's request prematurely anticipates an unfavourable outcome at the immigration admissibility hearing, and it would not be appropriate to stop an independent body from carrying out its statutory mandate.

"All of the possible harms discussed are speculative at best," Collicutt told Boswell.

She said if the division rules against Abdi, he does have some options, including obtaining a temporary work permit and asking for a judicial review.

But Perryman said Abdi shouldn't have to spend more time "going through bureaucratic processes to try to regain a status that he should have had in the first place."

"All of these take a significant amount of time and energy," he said outside of court. "I think from Mr. Abdi's perspective, he wants to try to reintegrate into Canada -- go to work as he is today in Toronto."

Perryman has said Abdi is currently employed as a research assistant and community youth leader, working on a research project that studies "crossover youth" -- young people who are involved with both the child welfare and criminal justice systems.

"I understand that his role is going to be working with a youth facilitator to organize meetings and gatherings of crossover youths to hear directly from them what types of resources, programs and issues face crossover youths," he said in an interview on Wednesday.

"Mr. Abdi was brought in on this project because of his lived experience. Because he himself was a crossover youth, he can relate to the experience that other children are going through."

Perryman said if the division makes a deportation order, Abdi would not be deported immediately. Because he is a refugee, the government would have to get a "danger opinion" before he could be deported, said Perryman.

Abdi's constitutional challenge is still in its early stages.

His case has become a rallying point for advocates who say it was wrong for the province to fail to apply for citizenship on his behalf. Roughly two dozen supporters attended the proceeding Thursday.

Perryman has said deporting Abdi to Somalia -- a country to which he has no ties and where he would be unable to care for his Canadian-born daughter -- would be unfair.

Abdi was born in Saudi Arabia in 1993. After his parents divorced, his mother -- fearing persecution if she returned to Somalia -- fled to Djibouti, where the family obtained refugee status.

His biological mother died in the refugee camp when he was four, and two years later he came to Canada with his sister and aunts.

But shortly after arriving, the children were apprehended by the Nova Scotia government. Abdi's aunt's efforts to regain custody were rejected, and her attempt to file a citizenship application for the children blocked.