She Xianglin, who was wrongly convicted of murdering his wife in 1997, talks to reporters after being released in 2005. WU WANSHENG / FOR CHINA DAILY

"Every day seemed like a year at that time," Gongsun said. "But I still believed in justice and the law, so I encouraged the sister to persevere."

On Oct 28, 2010, the top court disapproved of Nian's death sentence because of insufficient evidence.

But the intermediate court still sentenced the man to death, after the high people's court returned the case to it for the rehearing in 2011.

"It was unbelievable and I was extremely upset," Zhang said, adding that it was rare to see a court give the death sentence again after the highest-level judicial department disapproved its verdict.

"I was confused and organized more lawyers to discuss the case," Zhang said.

A team of more than 30 lawyers later participated in the case, providing their judicial opinions and pro bono legal aid for Nian's family.

"Non-legal elements may have interfered with the case because a court won't keep a problematic verdict if the prosecutors' evidence had flaws," Zhang said.

She said she was also deeply moved by the sister, who quit her accounting job and did not miss any opportunity to prove her brother's innocence.

"Pursuing justice is not the privilege of the minority. I wanted to accompany the sister to witness the rule of law," Zhang said.

Meanwhile, Nian Jianlan treated the lawyers as family.

The lawyers took the sister to Hong Kong, searching for professionals specializing in identification of poisons.

They also helped provide mental and emotional support.

"They didn't miss any call of mine, night and day, even during Spring Festival. Aside from legal aid, they provided me with the biggest comfort, especially after my parents died during my brother's case," she said.

"Thanks to the lawyers' persistence, I was not alone."

She is now accompanying her brother for physical checks on his stomach, hands and feet in the capital's hospital. Nian Bin has suffered from muscular atrophy and serious headaches after he returned home.

"But what we need most is to find the real murderer. Otherwise, my brother can't really free himself from the shame, the hatred from the victims' family can't be eliminated and our life won't be peaceful," she said.

The intermediate people's court and local police have not replied to the queries.

Larger significance

Zhang Lei, a member of the legal team, is busy with two other similar cases.

A man in Guizhou province got a life sentence and has served almost 20 years in prison for murder, but he has been crying for redress.

"Evidence in the case is insufficient and the man has also been tortured," Zhang said.

A woman in Jilin province also called Zhang after hearing about the lawyer's role in Nian Bin's case. She said her classmate was sentenced to death with probation for homicide and jailed 19 years.

"She told me she was encouraged by Nian's case, hoping to help the classmate whose parents had died," Zhang said.

The Jilin provincial high court had confirmed further investigation of the case but Zhang said cracking down on torture, often meted out behind similar cases, had more significance.

"The torture can be said to be the root cause of wrongful verdicts," she said.

Sun Jungong, the top court's spokesman, agreed and said Nian's case asks each court to reach an agreement - that a man cannot be jailed easily when evidence is insufficient and the facts are unclear.

"The agreement will help judicial bodies strictly provide judgments independently, effectively reducing false, unjust and wrongful cases," Sun said.

Gongsun Xue, who graduated from China University of Political Science and Law, suggested that legal departments highlight the importance of scientific evidence.

"Evidence appraisal also requires every judicial officers' attention," she said. The greater the exploration and study of evidence, the more effectively the truth will be uncovered, she said.

She also agreed that specialists should be tapped to hear and provide opinions in trials because their knowledge can help correct a verdict heading in the wrong direction.

But Si Weijiang, who has been involved in the criminal defense for Nian Bin since 2013, was not optimistic. He does not think Nian's acquittal is the end of the case.

"Only when police find the real murderer in accordance with the law can we mark a full stop for the case," Si said.

The protection of those on death row should also be taken into consideration, he said.

"The rule of law also lies in the respect we give to people sentenced to death."