A third of court-ordered work placements handed down to offenders failed to get under way within a one-week target, the Scottish Conservatives have claimed.
More than 800 convicted criminals waited in excess of two months before they could start community payback orders (CPO), according to a freedom of information request for 2017/18.
Scottish Government guidelines require offenders to begin their community service within seven working days of getting a CPO from a judge.
However, official figures show that one in three work placements missed this target while one person waited 469 days between being handed the order and starting work.
The Scottish Conservatives, who submitted the request, warned that SNP plans to scrap prison sentences of less than a year would increase problems with the CPO system.
Tory justice spokesman Liam Kerr said: “These are deeply worrying statistics and show that hundreds of criminals are waiting months before starting their CPO.
“It is ludicrous that a criminal could wait over fifteen months before starting to serve the sentence that was handed down to them, and something needs to change.
“These figures make a mockery of the seven-day target and with this SNP government recklessly pushing ahead with scrapping prison sentences of under a year they could add nearly 10,000 more criminals into the CPO system.
“It’s further proof of the problems that are being caused by the SNP’s soft-touch approach to justice.
“It’s time that Nicola Sturgeon and her party put victims first and finally abandoned their plans to stop dangerous criminals from serving jail sentences.”
A spokesman for Justice Secretary Humza Yousaf said it was “another example of rank hypocrisy from the Scottish Tories,” pointing out that the UK Justice Secretary David Gauke backed the proposals.
He added: “Even the UK Prisons Minister Rory Stewart admitted last year that they have a lot to learn from Scotland specifically on alternatives to ineffective short-sentences.
“Effective use of CPOs has contributed to a 19-year low in reconviction rates and funding of over £100 million for criminal justice social work has been protected in the draft budget for 2019-20.
“Around seven million hours of unpaid work have been carried out since community payback orders were introduced, delivering real benefits to communities.”