Deterrence as a stated purpose of punishment
In a discussion of incarceration, Bob Zadek lists four purposes of imprisonment: preventing further crime by putting the perpetrator away, rehabilitation, retribution, and deterrence, which he glosses as the idea that if you fear getting caught, you will not commit the crime. He then argues that applying those four tests to the incarceration of drug users flunks every one of them, calling the very purpose of incarceration silly and the wrong cure for the wrong problem Crime Down: Prison Costs Up (2011).
Veronique de Rugy takes up the deterrence limb specifically. She observes that the threat of jail works poorly for people who are poor, because what they give up by going to jail is not that much; she notes that they may be fed there, while conceding that prison violence is dramatic. She connects this to the fall in crime rates across the board for property crimes and murders as society became wealthier in the 1980s and 1990s, attributing the decline to people having more to lose, and concludes that the people with the least to lose by being thrown in jail are poor people, making the system unbelievably unfair to them. Zadek closes the exchange with a California story about a man who robbed a bank for a dollar because he wanted the healthcare he would get in jail Crime Down: Prison Costs Up (2011).
Sentence length versus certainty of apprehension
Rachel Barkow frames the growth of imprisonment as a product of political dysfunction rather than crime levels. Running for office rewards looking tough on crime, and the soundbite-friendly move is to promise increased sentences, on the assumption that this will help. She states that it does not: people are not deterred by an increase in a sentence from five years to seven years, and there is mounds of research on the point. What matters for deterrence, she says, is whether people are going to get caught, not the sentence length Rachel Barkow on Fixing the Fundamentals of Criminal Justice (2019).
Barkow extends the argument to pre-trial detention. Of the 2.2 million people incarcerated, almost 500,000 are detained pre-trial without having been convicted of anything. She attributes the high numbers to the same political dynamic: prosecutors ask for detention because they do not want to look like they are cutting somebody a break, and it is useful to them to get people to plead guilty, since a defendant will plead to anything to avoid staying longer in jail. Judges, for their part, do not want a campaign ad highlighting a case where they released somebody pre-trial who then committed another crime. She adds that sentences are dramatically out of whack for any public safety agenda, with people incarcerated well past the point at which they are likely to commit further crimes, so that an American prison today looks like a geriatric ward Rachel Barkow on Fixing the Fundamentals of Criminal Justice (2019).
Zadek reframes the tough-on-crime platform as a promise to take away more people’s liberty and lock up more people in cages than an opponent would, and notes that prisoners lack a strong voting lobby. He invokes Frédéric Bastiat’s phrase for them, the great unseen, locked away where nobody can see them Rachel Barkow on Fixing the Fundamentals of Criminal Justice (2019).
Hate-crime enhancements and the thrill-seeking offender
On hate-crimes legislation, Zadek raises empirical data on motive. He cites an undisputed finding that two-thirds of hate crimes committed, on admittedly spotty data, were done by people whose primary motive was thrill-seeking, and says that was the case in the Matthew Shepard case. From this he concludes that if you have a thrill-seeker, the thrill would probably be enhanced as the stakes go up, so there is no data to support the fact that there will be a deterrence; the measure is, in his words, simply a case of power politics, with the gay/transgender lobby able to get federal law amended to include them in the special class Hate Crimes Legislation (2009).
Jacob Sullum adds a separate mechanism by which such legislation might increase rather than reduce harm. By catering to particular groups and including them in legislation, the government may stir up more hatred by creating the perception that these people are being put in a special class above others and get special treatment under the law. He says it is no exaggeration that they are getting special treatment, and that it is not hard to see how somebody who already hates gays or hates disabled people might hate them even more as a result. He labels this hypothetical and says there is no evidence of it either, but calls it one possible outcome Hate Crimes Legislation (2009).
Sullum also describes the lobbying dynamic: certain groups already have special protection under the law, so others ask why they should not also have it. He says it would be better not to give anybody any special treatment, but once people start to get it, the groups left out see it as a sign that they are less respected or that crimes against them are taken less seriously, so the process feeds itself. Zadek predicts that pretty soon every group will be included, and jokes about a federal law imposing enhanced penalties for violent crime against anybody except lawyers Hate Crimes Legislation (2009).
Deterrence in foreign policy
John Glaser, described as Director of Foreign Policy Studies at the Cato Institute, discusses the U.S. network of overseas military bases. He states that there are roughly 800 overseas bases of various sizes in about 70 countries, amounting to about 260,000 troops and military officials, with annual costs estimated at $60 billion to $120 billion per year, a range he attributes partly to the Pentagon’s opacity in accounting and to multiple contradictory yet legitimate ways of counting Rethinking Pax Americana with John Glaser (2017).
Glaser separates what the bases are not for from what they are for. Defending the nation, in the sense of protecting U.S. territory and citizens from foreign attack, is explicitly not their purpose. He narrows the strategic rationales to three: deterrence, reassurance, and contingency responsiveness. Deterrence is trying to scare an adversary into not doing something, as with bases in South Korea, which are supposed to deter North Korea from invading South Korea. Reassurance is meant to convince friends and allies that the U.S. will come to their defense, with the presence of bases and troops bolstering the credibility of those promises. Contingency responsiveness, which he calls a big silly wonk word from the Pentagon, means getting places quickly, so that bases and troops in every nook and cranny of the planet can deploy and intervene quickly Rethinking Pax Americana with John Glaser (2017).
Deterrence and mass surveillance
Jonathan Hofer addresses automatic license plate readers and the deterrence claim made for them. He says that, broadly, he is optimistic that given sufficient safeguards ALPRs could be used to help law enforcement address crime, but that as they are used in California especially, and nationally, he does not believe they justify their current use. Without safeguards, he calls them an inherent civil liberties risk, and says the benefit to law enforcement is minimal to non-existent The Mass Surveillance nobody is talking about (2022).
On deterrence specifically, Hofer says the tools are not demonstrated to be very effective: studies have shown that they fail to deter things like car thefts and do not provide a general crime deterrence. He describes a study of the Piedmont PD, a small city surrounded by Oakland, whose cameras he examined because they kept basically the most complete data in the nation as far as he was aware. Their ALPR scans, he reports, do not correlate even with stolen vehicle recoveries, nor with investigative leads, which could include identifying a suspect, locating a witness, or spotting a stolen vehicle. He concludes that it is not time to write the technology off completely, but that it must be done right or not at all, and that right now it is not being done right The Mass Surveillance nobody is talking about (2022).
The same exchange appears in a second episode, where Hofer repeats the assessment in nearly identical terms: optimism about ALPRs given sufficient safeguards, the judgment that current use in California and nationally is not justified, the inherent civil liberties risk without safeguards, and the minimal to non-existent benefit to law enforcement. He again cites studies showing the tools fail to deter car thefts and provide no general crime deterrence, and again reports that the Piedmont PD’s ALPR scans do not correlate with stolen vehicle recoveries or investigative leads A PSA on ALPRs (2022).
Across episodes: the recurring test of evidence
The topic recurs across the excerpts, and the treatment is consistent rather than developing. In the 2009 hate-crimes episode, Zadek and Sullum question whether enhanced penalties can deter thrill-seeking offenders and warn that special treatment may inflame rather than reduce hostility Hate Crimes Legislation (2009). In the 2011 episode on crime and prison costs, Zadek lists deterrence among four purposes of incarceration and finds it flunks for drug users, while de Rugy argues the threat of jail is weakest for those with least to lose Crime Down: Prison Costs Up (2011). In 2017, Glaser names deterrence as one of three stated rationales for overseas bases while noting that defending the nation is explicitly not among them Rethinking Pax Americana with John Glaser (2017). In 2019, Barkow supplies the sharpest formulation, that certainty of apprehension rather than sentence length drives deterrence Rachel Barkow on Fixing the Fundamentals of Criminal Justice (2019). In the 2022 episodes on license plate readers, Hofer reports that the technology fails to deter car thefts or crime generally The Mass Surveillance nobody is talking about (2022) A PSA on ALPRs (2022). The later episodes do not revise the earlier ones; they apply the same evidentiary skepticism to new domains.
What the sources do not cover
The excerpts do not present any systematic theory of when deterrence does work, nor any empirical study defending a deterrent effect for the policies discussed. They do not state the outcome of any case, the name of any bill, or the amendment on which any measure turned. Several excerpts break off mid-sentence or mid-thought, and nothing beyond those points is reported here.