In his evidence, Peter Guenther, former executive-director of the Regional Psychiatric Centre in Saskatoon, said the incidents involved a correctional manager, John Tarala, in March 2007.
Tarala had intervened to stop Smith from tying ligatures around her neck.
"I determined (he) had grabbed her by the hair and lifted her off the ground and had also used very inappropriate language during this use of force," Guenther wrote in his incident report.
"Regardless of how difficult and challenging this offender's behaviours are, the staff knew that there was nothing that justified an assault or the abuse that is alleged."
In addition, the report notes a nurse who witnessed the incident said Tarala had ordered her to falsify her report.
Tarala offered to resign but Guenther said he could not accept it.
"I asked Mr. Tarala if he was offering his resignation because he had done something wrong and he replied that he had been working long hours and probably did some things that he should not have done," Guenther stated in his memo.
Following a disciplinary proceeding, Tarala was fired for the incidents.
However, criminal prosecution against him ultimately failed in part because Smith had died in the interim and the judge would not allow her written allegations as evidence given that cross-examination was not possible.
Ten days after Guenther's report to his superior, Smith was put on a plane to a facility in Montreal. She had been at RPC for four months.
Guenther testified the alleged assault was the "precipitating incident" for the move, but a transfer assessment did not mention it.
Despite the challenges, Guenther said Smith would likely have remained at RPC if not for the incidents involving Tarala, which created a tense atmosphere.
Now retired, Guenther told the inquest Smith didn't seem to care she could be doing permanent harm to herself by tying ligatures around her neck.
He needed a moment to compose himself as he testified that he was present when a nurse explained to Smith that oxygen deprivation could kill brain cells or damage her eyes.
Smith's response, Guenther said, was: "Whatever."
Guenther, who was effectively warden at RPC, said the teen's intensity and sustained level of self-harm was unlike anything he had ever experienced.
Within days of her arrival from Nova Institution in Truro, N.S., she started tying ligatures around her neck, sparking a cycle of forceful interventions, including one in which she complained Tarala stepped on her head.
"We'd make some gains for a period of time, then not so much and she would revert to her previous behaviour," Guenther testified.
One good period occurred in the days before, during and after a visit by her mother from New Brunswick, the inquest heard.
The self-harming appeared to be attention-getting behaviour, so Guenther's directive was to be matter-of-fact in removing the ligatures.
"Go out and save life, but save the drama," he said he told them.
Guenther discussed his opposition to "invasive" searches given Smith's ingenuity in obtaining ligatures and hiding them in her body cavities.
"You could conceivably do this many times a day," Guenther testified. "The futility of this occurred to me."
While guards used inappropriate force on Smith on several occasions, he said, at times the teen readily admitted they were right to be forceful.
"I kicked the officer. Yes I assaulted her. They did what they needed to do so I would stop," Smith told Guenther after one incident.
Smith was sent to the custodial forensic psychiatry facility operated by Correctional Service Canada in December 2006 because authorities at the prison in Truro believed she would get intensive mental health treatment there.
RPC is the only federal correctional facility that takes female inmates with mental health issues.
The inquest has previously heard that staff at Nova couldn't cope with her.
After more than a dozen further transfers, Smith, 19, of Moncton, N.B., choked herself to death in her segregation cell in Kitchener, Ont., in October 2007. Guards — under orders not to intervene — stood by and watched.
Guenther faces further cross-examination on Thursday.