A Chinese court on Friday acquitted a death-row inmate who spent eight years behind bars for double murder in a high-profile case that observers say may be a rare exception in a court system riddled with wrongful convictions.

Citing insufficient evidence, the high court of the southeastern province of Fujian overturned the guilty verdict against Nian Bin, a grocery shop owner accused of fatally poisoning a fellow villager's two children in 2006. The case attracted some of China's most prominent lawyers and wide attention in social media.

"As far as we can tell, this is an isolated case, but we hope this will help China move forward -- even with a small step -- in building rule of law," Beijing-based legal scholar Xu Xin said. "We should thank his lawyers and their unrelenting efforts for the acquittal. The social media also have played a role, having put pressure on the court to hear the case fairly."

Nian was immediately freed after Friday's announcement. The 38-year-old met his family in a tearful reunion, according to photos posted on social media by supporters and his lawyers. Nian had repeatedly appealed his guilty verdict, with lawyers saying he was tortured into confessing to the crime.

In overturning the guilty verdict, the Fujian provincial high court said the prosecution had conflicting evidence, lacked proof that the victims died from rat poison and failed to adequately trace the origin of the poison. Xu said the defense team was able to successfully prove that some evidence was false and concocted by police.

Nian's lawyer Zhang Yansheng told Chinese state media Friday that the Fujian high court deserves credit for showing courage, rare in China's legal system, to correct the wrong.

"There are obvious mistakes and loopholes that judge clearly know but refuse to correct. Instead, they become the defenders of the prosecutors," Zhang said. "Sometimes I felt the judiciary system would rather sacrifice an innocent man to save its face."

Such acquittals are unusual but not unheard of in China. A man on a suspended death sentence was retried and acquitted in March 2013 in eastern Zhejiang province, and the rape-and-murder conviction of a man in central Hunan province was overturned the following month.

Responding to the rising anger at prevalent wrongful convictions, Beijing last year released detailed recommendations for preventing such unjust cases: Judges should presume defendants are innocent until proven guilty, reject evidence obtained through torture, starvation or sleep deprivation and refrain from colluding with police and prosecutors.

Legal scholars, however, remain skeptical about the prospects for deep changes to the courts, which remain under the control of the ruling Communist Party. They say political pressure to solve homicide cases often leads to wrongful convictions based on coerced confessions and fabricated evidence, and that courts lack independence to correct wrongs. Some murder cases have been thrown out only after the alleged victim turned up alive.

"The system keeps producing wrongful cases, and the courts -- lower in the hierarchy -- cannot rule independently," Xu said.

Shanghai-based legal scholar Zhang Xuezhong noted that the trial court convicted Nian two more times, siding with police, even after higher courts cast doubt on the case. He said the attention drawn to Nian's case helped him.

"It's a case of life and death, and the high court had little wriggling room when members of the public were watching closely," Zhang said.

Maya Wang, a Hong Kong-based researcher with Human Rights Watch, said it is too early to say if the acquittal signaled any judiciary improvement. She noted the court's reluctance to review Nian's torture allegations.

"It took much concerted efforts by some of China's best-known rights lawyers to get the current court to acknowledge that there is insufficient evidence," Wang said. "The true test of progress is how the judiciary will handle the aftermath of Nian's acquittal: Will it hold the police officers who tortured Nian accountable?"