By Geeta Pandey
BBC News, Delhi
Supporters of an Indian student raped and murdered 10 years ago have staged a protest in Delhi to demand justice in the case.
The Jessica Lal case provoked protests earlier this year
The man accused of killing Priyadarshini Mattoo was acquitted in 1999 because of a lack of evidence.
The judge said he knew the defendant, Santosh Kumar Singh, was guilty but was obliged to acquit him.
Mr Singh has always maintained his innocence. Supporters hope public pressure will lead to a retrial.
Earlier this year a public outcry at the acquittal of several men accused in the shooting dead of a Delhi model, Jessica Lal, resulted in the reopening of the case.
That case highlighted growing discontent in India at what many say is its ineffective law system, where high-profile perpetrators are almost never punished.
'Benefit of doubt'
About 100 supporters of Mattoo took part in the protest, which was widely publicised in the Indian media.
When the trial court judge acquitted Mr Singh in 1999 he said: "I know that he is the man who committed the crime. I acquit him, giving him the benefit of doubt."
The judge was scathing in his criticism of the investigating authorities saying they had manipulated evidence and ignored proper procedures.
Mr Singh's father was a senior police officer at the time and the judge said he may have interfered in the case: "The influence of the father has been there in the matter and there was deliberate inaction".
A public outcry followed the acquittal and the prosecution appealed against the verdict in the Delhi High Court in April 2000.
Mattoo's body was found in her Delhi flat in January, 1996. She had been was strangled and her body showed signs of 19 injuries.