A report, released by the Sentencing Advisory Council on Wednesday, found the number of older offenders (aged 60+) in Victorian jails almost doubled between 2010 and 2019.

It also found the number of offences perpetrated by older Victorians increased, suggesting the ageing population was not the only reason forcing the numbers up.

An increase in historical sex offence prosecutions is a factor in the increase, with almost one in five being sentenced in the higher courts 40 years or more after their offending.

And while age is taken into consideration during sentencing, it does not justify unacceptably lenient sentencing, especially for offences such as murder or rape.

The report also found that older women were less likely to commit an offence than their male counterparts, but those that did were more commonly sentenced to fraud and theft.

Older men were more commonly sentenced for sexual or violent offending, which carry a much longer sentence.

Older prisoners, now classed as 'special needs prisoners', have been recognised as proportionally the fastest growing age group in prison systems around the world.

Because of this the Sentencing Advisory Council believes advanced age should be a relevant sentencing consideration but should not dominate the final decision.

But at the same time, the frailty and age-related physical and cognitive challenges that can accompany advanced age are relevant to sentencing decisions.

"Sentencing courts must have confidence that appropriate dispositions, facilities, supervision and programs are available for men and women in this age group at every level of the sentencing hierarchy," the report concluded.

Offences by older Victorians:

* Traffic and vehicle cases almost doubled

* assault and cause injury cases more than doubled

* breaching intervention orders almost tripled

Australian Associated Press