Legal experts on Tuesday defended China's death penalty rules and said a high-profile case in which a murderer was re-sentenced to death was not influenced by public opinion.

In 2009, Li Changkui, 29, a farmer from a village in Southwest China's Yunnan province, raped and murdered a 19-year-old girl before killing her 3-year-old brother. The high people's court of Yunnan province sentenced him to death on Monday.

This was Li's third trial. He was sentenced to death at his first trial in the intermediate people's court in Zhaotong city in the province last July, but the verdict was commuted to a death penalty with reprieve by the high people's court of Yunnan in March this year.

Gao Mingxuan, a leading criminal law professor with Renmin University of China, said the review of the case "followed strict trial procedures", and the latest sentence, which overturned the previous ruling, was based on the re-examination of the case's facts and was a decision made in accordance with the law.

Gao said it is "completely correct" for courts to be prudent about handing down death sentences. However, "in this case, it was improper to give Li a death penalty with reprieve during the second trial".

He said the final verdict was not influenced by online opinion, and the judgment was in accordance with trial procedures and has full legal standing.

"To respect public opinion is different from being influenced by it," he said.

The case aroused much anger among netizens. By 5:30 pm on Tuesday, more than 122,000 micro-bloggers had posted their opinions about the case on Sina Weibo, a Chinese micro-blogging website.

Most of the comments supported giving Li a heavier sentence instead of his previous reprieve.

Before Li's case, the sentence of Yao Jiaxin, another high-profile murderer who stabbed a young mother to death to cover up a hit-and-run accident, also received huge public attention. The 21-year-old university student was executed in Xi'an, Shaanxi province, on June 7.

Tang Hongxin, a Beijing-based lawyer at Yingke Law Firm, said a sentencing should be supervised by the public but should not be changed in response to public objections.

"If courts change a sentence as a result of strong public opinion, then there is no judicial credibility," Tang said.

"So, as we are realizing the power of the public's supervision, we should think more about how to make better use of it, not allow it to intervene with the judicature," he said.