Mr Kejriwal was responding to a tweet by Delhi Commission for Women (DCW) chief Swati Maliwal about the rape of a seven-year-old girl in outer Delhi's Kanjhawla.
"There should be capital punishment for rapist within six months following which rape (cases) would be curbed. For this, Delhi government is ready to provide funds to set up new courts," Mr Kejriwal tweeted.
The DCW chief had said that to ensure rapists of minor girls get death penalty within six months, she was ready to work in her office and on the field non-stop.
Two juveniles had been apprehended for allegedly raping the minor on Saturday last, the police said yesterday.