Ways of Enforcing Rules and what is wrong with each Three parts to the job: Catch the offender and collect evidence Determine if he is guilty Punish him Criminal law: State actors are hired to do all of it Enforcers act in their interest, not our interest Many costs are imposed on others, so may be ignored And the cop has an incentive to sell the evidence to the criminal In their mutual benefit So we need mechanisms to prevent that Privately prosecuted criminal law: A private actor catches and prosecutes If his incentive is the reward, he may prosecute someone who is innocent If private deterrence, doesn’t work when the criminal does not know who the victim is Out-of-court settlement only works if the defendant can pay

Tort Law The victim or his agent catches and prosecutes Doesn’t work if The defendant can’t pay—is judgment proof If the chance of catching and convicting is low It would cost $2000 to identify and prosecute the offender whose tort cost me $4,000 And I would have only one chance in four of success The damage payment is doing three things at once Punishing the tortfeasor Rewarding the victim for successful prosecution Compensating the victim for his loss There is no reason why the same sum should be right for all three

Feud System Private and decentralized Problems The victim catches, prosecutes, and enforces the verdict Policeman, judge, jury and executioner. Sounds dangerous Problems It requires some commitment mechanism, to make me carry out my threat Unjustified or extortionate claims are limited by third parties If plaintiff and defendant really disagree about the claim Defendant has an incentive to resist, which can produce continued violence So you need some mechanism, such as arbitration That lets one side or the other give in without looking weak

Community responsibility system Prison gangs, Vitsa, Dia paying groups Smith vs Hume on established religion It requires some mechanism to enforce rules of behavior on the group members Prison gang: Like a government with criminal law Religious sect: Like norms, ostracism, similar non-violent enforcement

Reputational Enforcement If you act in ways that make dealing with you costly Other people choose not to deal with you, which is a cost to you Not to punish you but to protect themselves Which depends on their knowing who is at fault If they cannot tell, they avoid both parties to the conflict Which makes complaining that someone cheated you unprofitable So you don’t, so reputational enforcement doesn’t work Which is an argument for some way of lowering information costs Reputational enforcement depends on repeat dealings But most of us interact with other people in many ways If I cheated you in one way, others may distrust me in other ways

Enforcement by the Threat of Ostracism Making it work faces a public good problem Why should I give up opportunities to associate with someone Just because other people want to punish him? Solution: If you associate with him, you get ostracized too Depends on a society sufficiently isolated so he needs to associate with fellow members Enforcement of private norms works largely by the same mechanism

Religion as an Enforcement Mechanism Obey the rules because God wants you to Supernatural pollution that is contagious Oaths as lie detectors Divine intervention—trial by combat or ordeal Leeson argues that, in the Middle Ages, ordeals worked Most defendants believed in them, so only chose to undergo an ideal if they were innocent Priests knew that, so mostly rigged the ordeals to acquit Religious rules are obeyed because They are right God will enforce Other believers will enforce Test: Are the rules obeyed when nobody is looking Romani quote implies that they sometimes are not

Potential Problems Someone has to interpret God’s will If someone else, he may interpret it in his interest If you interpret it yourself You may decide that what you want to do isn’t sinful Everyone is a biased judge in his own case If the reason to obey God’s will is fear of punishment, it only works if God is really there and punishes, or … Whether you are punished is not observable by you or others

Conclusion All of the alternative ways of enforcing rules have problems So which is best probably depends On the details of the society

Incentive to Enforce and the Problem of Error Rules require an incentive to enforce or they don’t get enforced But there are also problems with too much incentive Of two sorts We may spend more resources enforcing laws than it is worth And a strong incentive to convict may lead to convicting the innocent Directly, because someone profits from doing so Indirectly The lower the standard of proof, the more guilty defendants get convicted Also more innocent defendants We try to prevent that by legal rules for separating innocent from guilty But it isn’t clear how well that works The U.S. has elaborate rules for jury trials but Almost all felony convictions are by plea bargains How would you estimate the rate of false positives in the criminal justice system? Apply a new technology to old cases: DNA testing Several attempts to do that suggest error rates of a few percent

Trying Too Hard: The Law of Torture The original medieval solution was an ordeal: Let God judge They abandoned that on theological grounds: We don’t get to order God around Replaced it with a very high standard of proof Evidence clear as the noonday sun Two eyewitnesses to the crime Or a voluntary confession At which point most criminals could not get convicted, so … They instituted the law of torture Once they had half evidence, such as one witness or good circumstantial evidence They could torture the defendant into confessing Confessing under torture wasn’t voluntary, so Stop torturing him, ask if he wants to confess, if he doesn’t torture him again

Other Versions Arguably, plea bargaining in the U.S. has the same logic Give defendants lots of rights in jury trials to avoid convicting the innocent Now jury trials take too long to use for all felonies, so Replace trial with confession, not by torture but the threat of higher penalties Jewish law was even stricter for capital offenses Not only required two eyewitnesses, but Witnesses who had warned the criminal in advance But the found various grounds for ignoring that requirement Islamic law requires two witnesses for a Hadd offense For Zina, four witnesses to the same act of intercourse But there are multiple alternatives with lower standards: Tazir, Shurta, … Some schools hold that in Tazir the judge can convict on his own knowledge