More than 170 students from Fudan University signed a petition pleading for leniency for a former postgraduate student who received the death sentence in February for killing his roommate by poisoning.

The students are mainly from the university's law and medical schools. They sent the petition to Shanghai High People's Court, asking the court to spare the life of Lin Senhao, 28, who was a medical postgraduate student at the university.

A law school postgraduate student surnamed Wu drafted the letter with a professor and other students. It said that Lin should be punished, but also noted he was not a ruthless killer.

Lin had done some good things and was not a cruel man, Wu said, and he should be given a chance to rebuild his life.

"We didn't want to interfere in the court's judgment, but just want to help commute the sentence of Lin," Wu told Beijing Times.

The students expressed their willingness to do their best to help the parents of Huang Yang, the victim.

Huang Guoqiang, Huang Yang's father, said he does not accept the petition, according to local media.

Huang Guoqiang insisted on maintaining the principle of a life for a life, which requires the death penalty for the murder.

Fudan University said the move was the personal action of students, and they are looking into this action.

"It was initiated by the students themselves, and we are paying close attention to it," Lu Xiaolu, a staff from the university's news office, said.

"The petition may be a kind of respect for life, and we really don't want to see another life taken away. But it cannot replace the punishment for a murder. Lin should pay for what he has done, though it costs a life," a doctoral student from the university's medical school who declined to leave his name told China Daily.

In the first trial on Feb 18, the Shanghai No 2 Intermediate People's Court sentenced Lin to death for intentionally murdering Huang Yang in April 2013.

According to the court, Lin killed Huang by spiking their dorm room's water dispenser with toxic N-Nitrosodimethylamine.

Exposure to the chemical can cause liver damage and affect the blood. Lin stole it from the lab at Shanghai Zhongshan Hospital, where he worked as an intern.

Lin insisted that his aim was only to play a prank for April Fools' Day, but that was rejected by the court. The court said Lin didn't confess his involvement until 12 days later, when fellow students reported him to police.

His family said they will appeal the verdict and seek a second trial.

The Shanghai Higher People's Court will handle the second trial, but the date has not been scheduled.

Many netizens said they couldn't understand the petition.

"Lin was a medical student and worked with toxic chemicals, so he knew better than anyone else about their danger. Meanwhile, he didn't provide any honest testimony when questioned by police. His intention is easily open to doubt," said a netizen called Into The Cloud.

Hong Daode, a criminal law professor at the China University of Political Science and Law, said the letter could hardly influence the court because these petitioners are schoolmates of defendant, making the petition letter fail to maintain a neutral stance.

If the defendant's crime was severe enough for a death sentence, it's not likely the court would alter the sentence, Hong said.