How are criminal sentences actually decided?

By applying published guidelines to the specific case — a structured process that is considerably more constrained than the common perception of judges choosing freely.

The Sentencing Council. An independent body producing guidelines for offences in England and Wales. Courts must follow a relevant guideline unless satisfied it would be contrary to the interests of justice — so departure is possible and must be reasoned.

The structured steps a guideline sets out:

Determine the offence category, by assessing culpability — how blameworthy the offender's conduct was — and harm — what was caused or risked. These produce a category.

Identify the starting point and range for that category, which the guideline states.

Adjust for aggravating and mitigating factors, which are listed. Aggravating factors include previous convictions, offending on bail, targeting a vulnerable victim and offences committed under the influence. Mitigating factors include remorse, good character, age and immaturity, mental health, and the offender's role.

Apply reduction for a guilty plea, which is a defined sliding scale — the maximum reduction, conventionally up to a third, is available only for a plea at the first stage of proceedings, reducing progressively thereafter. This is why the timing of a plea matters so much, and it exists to spare witnesses and court time.

Consider totality, where there are multiple offences, so that the overall sentence is just rather than a simple addition.

Consider ancillary orders — compensation, restraining orders, disqualification.

Give reasons, in open court.

The constraints outside the guideline: statutory maximum sentences; minimum terms for certain offences; and the sentencing purposes set out in statute — punishment, crime reduction, reform and rehabilitation, protection of the public, and reparation.

Why sentences frequently seem lower than expected:

Guilty plea reduction, which is applied after everything else.

Time served on remand counts toward the sentence.

Release provisions. A custodial sentence is not served entirely in custody — release arrangements are set by statute, not by the judge, and this is the largest single source of public misunderstanding about sentencing.

Unduly lenient sentence scheme allows certain sentences to be referred to the Court of Appeal.

General information, not legal advice.