Four men convicted of raping Nirbhaya, a 23-year-old Delhi physiotherapy intern, 2012 will hang on March 20, a Delhi court ruled Thursday. Their execution has already been deferred three times. The most recent date set for their hanging was March 3, but one of them Pawan Gupta, filed a mercy plea the day before. And like the three other convicts' mercy petitions, it was rejected.