How does the 15-month jail term for environmental protester Violet Coco compare to other sentences?

Activist's jailing for a peaceful protest has shocked many, as less than 6% of people charged with environmental pollution and property damage offences are sent to prison

Deanna Violet" Coco has been sentenced to 15 months in prison with a non-parole period of eight months for blocking a lane of traffic on Sydney Harbour Bridge during a climate change protest.

Her sentence handed down last week troubled human rights advocates, who called it incredibly alarming", and appears harsh when compared to recent sentences for serious offences issued by courts in New South Wales and Victoria.

There are few examples of offenders being jailed in New South Wales for even the most serious breaches of laws designed to protect the environment, either because the laws do not provide for custodial sentences for offenders or because they have not been applied.

There are a number of considerations made when imposing a sentence, including deterrence and the gravity of the offence - and many of these factors are set out in sentencing guidelines for magistrates and judges.