1980-2000, the age of death & feticide

Poking around the GSS for another reason I stumbled onto something weird. Something which I'd seen hints of, or seen referred to before, but never followed up myself. It seems that support for abortion-on-demand and the death penalty peaked concurrently in the span between 1980-2000. This is evident in two GSS variables, ABANY and CAPPUN, which ask if you support a woman's right to an abortion for any reason and the death penalty for murder. Additionally, I decided to look at attitudes toward homosexuality using HOMOSEX as a reference as a point of contrast. Unlike abortion or the death penalty attitudes toward homosexuality have been changing in the same direction for the past 30 years. Additionally, the magnitude of the change seems to be much greater than in regards to the other two controversial social issues, and especially abortion, which has exhibited notable stability. I was particularly interested in differences by religion, so I limited the sample to whites and broke it down by Protestant, Catholic, Jew and None. To reduce sample size volatility I clustered by decade, so that "1970s" is inclusive of every year in the 1970s that the GSS asked the question for that variable.