Vijay Bahadur Pathak, state spokesman of the BJP, said the former chief minister's comments were unacceptable and very sad.
Pathak said the statement of the SP supremo comes as a shock as he was very critical of rape cases during the Mayawati-led Bahujan Samaj Party regime in the state.
Noted lawyer Vrinda Grover said he was using the law to attack women's rights.
"Death penalty is an alibi for Mulayam Singh to attack the new law that recognises the integrity of woman's body. Right from the beginning, he and his party were creating impediments in the way of stringent laws to protect women. His utterances support the view that women have no rights over their body and they are something of a plaything for males," Grover said.
She said the former chief minister's utterances show how far behind he was of the present day youth. "It is incumbent upon the youth to ensure he is defeated in the election," she added.