More broadly, it was a time of tough attitudes toward criminal sentencing, years when three-strikes laws were popular and political leaders had declared a war on drugs.
Now, admittedly, FLG has his own biases and assumptions. But this sounds a lot like somebody trying to shift blame for a stupid policy, zero tolerance, conceived and enacted by a typically liberal institution, public school teachers and administrators, onto Republican and conservatives by insinuating that their policies toward criminals also applied to the schools. FLG doesn't know of any conservative, although there may be some, who were supportive of zero tolerance for bringing pocket knives or toy guns or sometimes even pictures of guns. Freaking out about guns, weapons, and violence is more a liberal thing than a conservative one. So, don't try to shift that onto the culture created by Republicans. The drug zero tolerance, however, FLG does know some conservatives who support, but not many. Most conservatives, and indeed most people generally, think that the adults in schools ought to use some common sense and judgment, not hard and fast rules like zero tolerance.
FLG blames increasing legalism, which deprives people in authority of discretion, for the zero tolerance, and he blames legalism, perhaps wrongly, on the liberals. So, you can take that zero tolerance hot potato right back, Donna St. George.