HALIFAX -- The Nova Scotia government apologized Wednesday to the friends and family of a prominent gay rights activist who was beaten to death outside a Halifax bar, promising that lessons will be learned from what happened to Raymond Taavel.

"His death will not be in vain," Leo Glavine, minister of health and wellness, told the legislature. "We are determined to ensure that positive change comes from this terrible tragedy."

Andre Denny, a patient deemed not criminally responsible for his own actions, was issued a one-hour unescorted pass from the East Coast Forensic Hospital on April 6, 2012, but didn't return.

While authorities were searching for Denny, Taavel was killed outside Menz bar on Gottingen Street following an altercation.

Denny, who is from Membertou, N.S., pleaded guilty to manslaughter in Taavel's death in November and will be sentenced in January.

He was originally charged with second-degree murder. Crown attorney James Giacomantonio said last month that a manslaughter conviction would fit the facts of the case.

Glavine says a review identified significant gaps where improvements were required to ensure the protection of the general public.

But he says the government has not been able to introduce a GPS tracking program for forensic patients on leave from hospital as suggested by Taavel's family.

"I understand their request, and we asked experts to research it," he said in a prepared statement. "And although we determined this particular action was not feasible, we have made many other changes that we believe will result in a lasting improvement.

"I hope Raymond's family will agree."

Taavel's family released a statement through their lawyer, saying they remain concerned whether patients deemed not criminally responsible can be found if they don't return to the hospital.

"It is the sincere hope of the Taavel family that the lessons learned from this tragedy are never repeated," it says.

Hundreds attended vigils for Taavel, who was remembered at the time by former Nova Scotia premier Darrell Dexter as a champion in the fight against discrimination, violence and intolerance.

Glavine said the changes that have been made will increase safety.

"Our work will never be complete, but it is my sincere belief that the changes brought about by this senseless tragedy will increase the safety of the general public and the quality of care for patients at the hospital," he added.