The line graph does not accompany Nicholas Kristof's op-ed in the print edition of the New York Times

When We Kill, by Nicolas Kristof.  (The New York Times, 6/14/2019)

President Trump is now calling for expanding the death penalty so it would apply to drug dealers and those who kill police officers, with an expedited trial and quick execution. A majority of Americans (56 percent, according to Gallup) favor capital punishment, believing that it will deter offenders or save money and presuming that it will apply only to the vilest criminals and that mistakes are not a serious risk.  [emphasis added]

All these assumptions are wrong.

Source:  Death Penalty Info