Li Jiangong, who fought a decadelong legal battle to revoke his death sentence, was exonerated and released on Tuesday by the local intermediate court for "unclear facts and insufficient evidence", his defense lawyer told China Daily.

"Li is now a free man, and we will turn our attention to seeking compensation in accordance with relevant rules and regulations and hold those who mistreated him during custody accountable," said Wang Shihua, Li's lawyer.

On Dec 3, 2007, local police found the body of Cao Juying, a 75-year-old retired worker, in a septic tank at a local cement factory in Korla, Xinjiang Uygur autonomous region, according to local court documents. A forensic report suggested Cao was murdered because she had tape sealing her mouth and nose, and there were marks on her head made by a blunt object.

Roughly a week later, Li, who was Cao's neighbor, was apprehended by police. The initial investigation said Li had argued with the elderly woman on Dec 1, then beat her to death with a wooden stick and threw her body into the tank.

In July 2008, the local court sentenced Li to death for intentional homicide with a two-year reprieve. Li and his family kept appealing to the Xinjiang high court over the last decade, claiming he was innocent but was tortured to confess during police custody.

"There are scars from the beating on Li's body that are still visible to this day," said Wang, who took Li's case in 2016. "There were also some serious deficiencies in the evidence, such as the lack of incriminating DNA or fingerprints, imprecise time of the murder and overemphasis on confessions drawn from police questioning."

Last December, the local high court confirmed Wang's concerns. It retracted the original ruling after re-examining the existing evidence and finding it to be inconclusive. The case was then passed to the Intermediate People's Court of the 2nd Division of Xinjiang Production and Construction Corps for retrial.

During a two and a half-hour hearing on Nov 24, the intermediate court said the two dozen incriminating confessions collected during police questioning of Li and his daughter, Li Juan, were illegal and could not be used in the trial. Key clues in the case, such as motive and objective, could not be established, and evidence such as the murder weapon, fingerprints and other evidence from the crime scene were also missing.

As a result, the court announced on Tuesday that there was not enough evidence to incriminate Li, and he was exonerated and released the same day.

"This case offered some closure to a battered family, and some hard lessons for China's local legal systems," Wang said. "Namely, police and prosecutors should uphold professional and evidence-based practices to avoid undermining public trust of the judicial process."

Wang said the real killer is probably still on the loose, but the lack of physical evidence and the passage of time would make it very difficult to find the real culprit.

"On the other hand, those who rushed to incriminate Li without sufficient evidence should be held accountable," he said.

"The law is the best tool to maintain peace and stability, but legal procedures must be carried out rigorously and professionally," he said.

"Only then can we prevent these types of unjust cases from happening."