A think tank has called for a ban on prison sentences of six months or less in Scotland.
Reform Scotland said only an outright ban on short sentences could bring about change in the justice system.
The organisation said the move should extend to a year if automatic early release for short sentences remains in place.
The Scottish government said it believed that only the most serious offenders should be jailed.
It does not want the courts to jail anyone for three months or less.
While judges are still able to pass sentences of under three months, legislation says they should only do this when no alternative is available or appropriate
Reform Scotland has raised concerns, however, that this policy is not being adhered to.
Three-month prison sentences accounted for almost 30% of prison terms in 2015-16.
In addition, the think tank said automatic early release meant 65% of offenders that year served three months or less.
Speaking ahead of the publication of a new report on prison reform, research director Alison Payne said: "The Scottish Prison Service itself has said that there are limited opportunities for rehabilitation during short sentences.
"Furthermore, the disruption of a short sentence, including loss of income and employment, and problems with childcare and family relationships, often makes the sentences disproportionate to the crime.
"A presumption against short sentences is well meaning but, in the final analysis, if we don't want short sentences then we have to prohibit them.
"People make mistakes and we need to help ensure that such mistakes are not repeated, not just because of the emotional and financial cost of crime to victims, families and society, but because of the loss of human potential.
"Such a view is neither ideological nor controversial, but is human and compassionate. However, it is not a view that is reflected in Scotland's sentencing regime."
But the Scottish Conservatives said short-term sentences still have a role to play in the justice system.
The party's justice spokesman Liam Kerr said: "Our experienced, highly trained sheriffs use these punishments for a reason, and removing their ability to do so and indeed their discretion - where they feel the facts fit that sentence - would be wrong.
"If criminals know they can turn up to court and won't be jailed, it will do nothing to deter them from illegal activity.
"Many people, especially victims of crime, already think Scotland's justice system is too soft touch and would view an abolition of these jail terms as an extension of that."
Last month, Scotland's chief inspector of prisons David Strang called for an end to jail terms of under a year.
Mr Strang said the current presumption against three-month sentences should be extended to 12 months, arguing the approach does not cut crime.
The Scottish Liberal Democrats have also backed ending jail sentences of under 12 months, urging the Scottish government to act following a 2015 consultation on strengthening the presumption against short-term sentences.
Ministers have consulted on extending the current presumption against three month sentences to 12 months, and hope to publish plans later this year.
A Scottish government spokeswoman said: "Our recent vision paper makes clear that Scotland's prison population remains unacceptably high.
"The associated plan sets out a range of actions we are taking to provide alternatives to ineffective short-term prison sentences and to prevent re-offending, for example through investment in community sentences and electronic monitoring, and learning from our successful preventative approach to youth justice.
"The Scottish government is committed to the principles of the McLeish Commission that imprisonment should be reserved for people whose offences are so serious that no other form of punishment will do and for those who pose a threat of serious harm.
"We believe that more can be done to strengthen the current presumption so that it has a more direct impact on sentencing decision, and have consulted on proposals to do just that.
"The responses to that consultation are informing our decisions and we have been taking time to consider these views, including discussions with relevant partners and other stakeholders."