"Minor punishment of seven years jail term will not be adequate for such an act ... Existing laws need to be amended to end the menace," Yadav said before setting out for his 'Parivartan yatra' against the alleged 'misrule' of the Nitish Kumar government.
Lalu said RJD would advocate for awarding death sentence to rapists when the issue of gang rape of the 23-year-old para-medic in a moving bus in New Delhi comes up for discussion in Parliament.
Rashtriya Janata Dal (RJD) has four members in Lok Sabha, including Prasad and two in Rajya Sabha.
He said the public outrage over the Delhi gangrape was justified as the victim was brutally assaulted and is battling for life.
In view of growing incidents of rape in Bihar and Karnataka, Yadav said stringent anti-rape laws were needed to prevent such barbaric crimes.