The Deterrent and Preventive Approaches

The evidence

Research findings should be stated carefully, and an answer that does so is much stronger than one that asserts.

Certainty deters, and the effect is real but modest. Increases in the probability of detection are associated with reductions in offending.

Severity has a weak effect at best. Studies of sentence increases repeatedly find small or no effects on offence rates, which is uncomfortable for the way deterrence is usually invoked in public argument.

The death penalty has not been shown to deter murder better than long imprisonment. This is the finding most relevant to the Indian material below. The honest statement is that the studies do not establish a marginal deterrent effect, not that they prove there is none.

Deterrence works better for planned than for impulsive offences, which follows directly from the assumptions above.

The objections

It permits punishing the innocent. If the object is the effect on the public, then the punishment of somebody believed guilty produces the effect whether or not they are.

It permits disproportion. A very heavy sentence for a common minor offence may deter more than a proportionate one. Only desert explains why that is not permissible.

It uses the offender as a means, which is Kant's objection.

It sits badly with the facts about who offends. If most offending is impulsive, opportunistic or driven by dependency, then the theory's central assumption fails for most of the cases it is invoked in.

Prevention or incapacitation

What it is

The offender is deprived of the opportunity to offend. Imprisonment is the ordinary means; disqualification from driving, from holding office or from practising a profession; forfeiture of the instrument of the offence; and, at the limit, death.

Its distinguishing feature. It does not depend on the offender's state of mind at all. A person who is incapacitated does not offend against the public whether or not they are deterred, reformed or remorseful, which is why the theory keeps its appeal in exactly the cases where deterrence fails.

The forms

Selective incapacitation, targeting those assessed as likely to reoffend.

Collective incapacitation, imprisoning a whole class of offender for longer.

Non-custodial incapacitation, which is much of what modern law actually does: disqualification, licence conditions, restraining orders, and prohibitions on holding particular positions. These are important for an answer because they show the theory operating without imprisonment.

The objections

It punishes for what a person may do. The theory's logic is prediction, and prediction about individuals is unreliable. Taken alone it justifies detaining a dangerous person who has committed no offence, which is punishment without a crime.

It is only as good as the prediction. Assessments of dangerousness produce both false positives, people detained who would not have offended, and false negatives, and the cost of the first falls on the person detained.

It is expensive and displaces. Incapacitating one offender in a market offence often results in another taking their place, so the offence rate is unchanged.

Its logic has no natural stopping point, which is why every system that uses it caps it with desert.

Prison itself may increase the danger. If the sentence makes the person more likely to offend on release, incapacitation has bought a period of safety at the cost of a longer risk.

The two theories in Indian sentencing

Facts. Bachan Singh v. State of Punjab, (1980) 2 SCC 684. A Constitution Bench considered the validity of the death penalty for murder in section 302 of the Penal Code and of the sentencing procedure in section 354(3) of the Code of Criminal Procedure 1973, which requires special reasons for a death sentence.

Held. Both provisions were upheld, with the rule that for persons convicted of murder life imprisonment is the rule and the death sentence an exception, that a real and abiding concern for the dignity of human life postulates resistance to taking life through the instrumentality of the law, and that this ought not to be done save in the rarest of rare cases when the alternative option is unquestionably foreclosed.

Facts. Machhi Singh v. State of Punjab, (1983) 3 SCC 470. A feud between two families produced seventeen deaths in five incidents in five neighbouring villages in Punjab on the night of 12 and 13 August 1977, the dead and injured including men, women and children related to one Amar Singh and his sister Piaro Bai. Machhi Singh and eleven others were prosecuted in five sessions cases, he being the common accused in each. Four were sentenced to death and nine to life imprisonment, and the death sentences were confirmed by the High Court.

Held. The Court explained the rarest of rare formula and set out guidelines for identifying such cases, grouping the relevant considerations under the manner of commission of the murder, the motive, the anti-social or socially abhorrent nature of the crime, its magnitude, and the personality of the victim. It directed that aggravating and mitigating circumstances be drawn up and balanced, and that death be imposed only where the option of life imprisonment is unquestionably foreclosed.

Why the two cases belong in this chapter. They are where the deterrent and preventive arguments were put to an Indian court and were not allowed to decide the matter. Deterrence was pressed and did not make the death penalty the ordinary sentence for murder. Incapacitation is achieved by life imprisonment, which is why the Court could treat that as the rule. And the guidelines in Machhi Singh are drawn from the offence, that is, from desert, rather than from any prediction about the offender's future conduct, which is desert limiting the forward looking theories in practice.

A worked example

A State faces a rise in road accidents caused by drunk driving and considers three measures: raising the maximum sentence from six months to three years; buying breath analysers and deploying them at random on twenty roads every night; and disqualifying convicted drivers from holding a licence for five years.

The first is severity. It raises the penalty for those convicted, and the evidence that severity alone changes behaviour is weak. If the present chance of being stopped is very small, tripling a penalty that is almost never imposed changes the expected cost of drunk driving hardly at all.

The second is certainty, and on both Bentham's reasoning and the modern evidence it is the measure most likely to work. Random and visible testing changes the driver's estimate of being caught, which is the multiplier in the calculation.

The third is incapacitation. A disqualified driver cannot lawfully drive, so the theory operates without any change in their attitude at all. Notice that it is non-custodial, which shows incapacitation does not require prison, and notice its weakness: it works only so far as disqualification is enforced, since a person determined to drive can drive without a licence.

A combined answer. Certainty first, because it changes the calculation; disqualification second, because it works on those the calculation does not reach; and the increase in maximum sentence last, capped by what the offence deserves, because it addresses the smallest of the three variables.

Distinctions that carry marks

What these approaches are NOT

Deterrence is not vengeance. It is entirely forward looking and is indifferent to desert, which is its problem, not its similarity to retribution.

Prevention is not preventive detention. Incapacitation as a theory of punishment follows conviction for an offence. Detention on the basis of what somebody may do, without an offence, is a different thing and raises different constitutional questions.

A prison sentence is not evidence for one theory over the other. It deters, incapacitates, and is said to reform, which is precisely why the theories must be separated when they are being assessed.

"Deterrence has failed" is too strong. The accurate statement is that certainty deters and severity does so weakly, and that most public argument invokes the variable with the weakest support.

Quick revision

1. Deterrence operates on the will; prevention operates on the capacity. A prison sentence does both, which is why they are confused.
2. General deterrence aims at the public and was Bentham's chief end; special deterrence aims at the offender.
3. Assumptions: a rational calculator, who knows the penalty, believes in the risk of detection, is in a state to calculate, and has alternatives.
4. Three variables: certainty, severity, celerity. Certainty matters most, on Bentham's reasoning and on the evidence.
5. Evidence: certainty deters modestly; severity weakly at best; the death penalty has not been shown to deter murder better than long imprisonment; deterrence works better on planned than on impulsive offences.
6. Incapacitation does not depend on the offender's state of mind at all, and has non-custodial forms: disqualification, forfeiture, restraining orders.
7. Objections: deterrence would punish the innocent and permits disproportion; incapacitation punishes for what a person may do, depends on unreliable prediction, and has no natural stopping point.
8. Bachan Singh made life imprisonment the rule and death the exception; Machhi Singh supplied the guidelines, drawn from the manner, motive, anti-social nature, magnitude and victim, that is, from the offence rather than from prediction.

Test yourself

1. Distinguish the deterrent from the preventive approach. Deterrence operates on the will, seeking to dissuade by making the prospect of the penalty unattractive, and it therefore requires an offender capable of calculating. Prevention operates on the capacity, removing the ability to offend by imprisonment, disqualification, forfeiture or death, and it works whatever the offender thinks or feels. A prison sentence achieves both at once, which is why the two are constantly run together, but they are justified by different arguments and fail in different ways.

2. What does deterrence assume, and when do the assumptions fail? That the offender is a rational calculator who weighs expected gain against expected cost; that they know roughly what the penalty is; that they believe there is a real chance of detection; that they are in a state in which calculation can operate; and that they have lawful alternatives. The assumptions fail for offences committed in rage, under intoxication or compulsion, by the very young, where detection is so improbable that the penalty has no expected cost, and where the offender has no lawful means of subsistence.

3. Rank certainty, severity and celerity, and explain the consequence for India. Certainty first, then celerity, then severity. The expected cost of an offence is the penalty discounted by the probability of its being imposed, so a modest penalty that is very likely deters better than a heavy one that is unlikely. The consequence is that in a system with low conviction rates and long delays, raising sentences adds severity to an expectation already close to zero, while investment in investigation, prosecution and speed changes the multiplier and therefore changes behaviour.

4. State the objections to the preventive approach. That it punishes for what a person may do rather than for what they did, so that taken alone it justifies detaining a dangerous person who has committed no offence at all. That it depends on predictions of dangerousness that are unreliable, producing false positives whose cost falls on those wrongly detained. That in market offences it merely displaces, another person taking the incapacitated offender's place. That its logic has no natural stopping point, which is why every system caps it with desert. And that imprisonment may itself increase the risk on release.

5. How do Bachan Singh and Machhi Singh limit these approaches? Bachan Singh upheld the death penalty and the special reasons requirement while ruling that life imprisonment is the rule and death the exception, imposable only in the rarest of rare cases when the alternative option is unquestionably foreclosed, so the deterrent argument did not make death the ordinary sentence for murder and incapacitation was treated as achieved by life imprisonment. Machhi Singh then supplied guidelines drawn from the manner of the killing, the motive, the anti-social nature of the crime, its magnitude and the personality of the victim, all of which are features of the offence rather than predictions about the offender, which is desert limiting the forward looking theories in practice.