The protesters are also fed up with corruption, nepotism and other perceived injustices and have seized on the tribunals to express their dissatisfaction, he said.
In response to the demonstrations, the government sent a bill to Parliament that would amend the law creating the tribunals, allowing the prosecution to appeal if it felt a sentence handed down was too lenient.
Law Minister Shafique Ahmed said the bill was expected to be passed by Parliament on Sunday, and the government has said it would use it to appeal Mollah's sentence.
One legal analyst, Shahdeen Malik, said the amendments would strengthen the law, and that the country's legal system could be counted on to give verdicts based on evidence and not simply in response to street pressure.
But New York-based Human Rights Watch criticized the proposed amendments, saying that passing retroactive laws to overturn unpopular verdicts violated the country's commitments to protect the rights of defendants.
"Convictions of those responsible for the 1971 atrocities is important for the country, but not at the expense of the principles that make Bangladesh a democracy," said Brad Adams, Asia director at Human Rights Watch.
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