Jerome O'Callaghan, "Under the Influence: Pornography and Alcohol - Some Common Themes" Akron Law Review v29 (Fall, 1995) 35-56
which is an especially clear development of one such analogy.
Consider the details involved in the logic of punishing the drunk driver. At some point the political community must accept the following axioms:
a1) alcohol, when consumed, impairs motor function;
b1) the presence of alcohol in the body can be accurately detected and measured;
c1) a direct and causal relationship exists between the volume of alcohol consumed and the degree of impairment;
d1) the higher the degree of impairment the greater the risk of injury to self or others;
e1) there is, for most people, a relatively safe amount of alcohol in the blood, and this amount can be measured;
f1) based on this measurement a threshold can be identified beyond which activities which involve motor function (such as driving) become significantly more dangerous;
g1) knowing the impairment effect of alcohol to be temporary, the danger of an impaired individual is also temporary.
Now consider a similar set of axioms, this one explaining the logic of pornography reform:
a2) pornography when consumed impairs "social judgments";
b2) the presence of pornography's influence on the mind can be accurately detected and measured;
c2) a direct and causal relationship exists between the volume of pornography consumed and the degree of impairment;
d2) the higher the degree of impairment the greater the risk of injury to self or others;
e2) amounts of pornography that are relatively safe, for most people, can be measured;
f2) based on this measurement a threshold can be identified past which activities such as social interaction become significantly more dangerous (i.e., the public suffers an elevated risk);
g2) assuming the impairment effect of pornography to be temporary, the danger of an impaired individual is also temporary.
* * *
Some anti-pornography reformers allege that all pornography pollutes, and so the issue of volume consumed is irrelevant. For this group axioms a2) through g2) can be reduced to these simple propositions
a3) pornography impairs social judgment;
b3) the presence of pornography in the mind/person can be accurately determined;
c3) the distribution and/or consumption of pornography is itself an elevation of risk to the public which warrants sanction.
(Excerpt from pages 39-41)
The rest of O'Callaghan's article critiques the arguments and notes some of the limitations of the analogy.
One of the best discussions of drug and alcohol regulation is the aptly titled:
Mark A.R. Kleiman, Against Excess: Drug Policy for Results (New York, NY: Basic Books, 1992).