The rigorous examination of the deterrent effect of capital punishment began with research in the 1970s by Isaac Ehrlich, currently a University of Buffalo Distinguished Professor of Economics.[12] Professor Ehrlich's research found that the death penalty had a strong deterrent effect. While his research was debated by other scholars,[13] additional research by Professor Ehrlich reconfirmed his original findings.[14] In addition, research by Professor Stephen K. Layson of the University of North Carolina at Greensboro strongly reconfirmed Ehrlich's previous findings.