RADICAL plans to shut courts across Scotland to save money are "fundamentally flawed", sheriffs have warned.

In an outspoken attack on the restructuring of the country's court service, which is being backed by the SNP government, the Sheriffs' Association said key proposals are simply "not feasible".

The Association said it is unclear whether the surviving courts could cope with all the business which would be transferred to them, and said the proposed savings are based on incomplete figures.

The comments come in a response to the Scottish Court Service's consultation on the restructuring, which will see 10 of the 49 Sheriff courts and seven Justice of the Peace courts close by January 2015 to save £1.3 million a year. Mainland jury trials are to be held at just 16 sheriff courts, with the rest dealing with summary cases and civil work.

Holyrood's Justice Committee is due to hold hearings on the shake-up next month.

The proposals attracted widespread criticism when they were published last year, with warnings that centralising court services would undermine local justice and leave jurors and witnesses facing long and costly journeys.

Despite the opposition, the Court Service announced earlier this month that it would press ahead with the closures. After just 10 days considering their report, Justice Secretary Kenny MacAskill agreed, saying the changes were "compatible with our wider justice reforms".

The Sheriffs' Association says the idea is "fundamentally flawed" as there is no definition of the work the courts would carry out, thus no way of knowing if they could cope, what staff would be needed, or the costs involved.

The shake-up has also led to a cabinet split, with Education Secretary Michael Russell fighting changes in his seat, Argyll and Bute, which is one of the hardest-hit areas.

In his consultation response, Russell said the loss of services will add to the "hardship of island communities and – potentially – to their depopulation". However, when the issue was put to a vote at Holyrood on Thursday, he observed the tradition of collective cabinet responsibility and backed the plans.

Labour Justice spokesman Lewis Macdonald said: "If a cabinet colleague tells you you're wrong then that should be heeded by any minister. And the idea that you just ignore the views of those who operate the justice system is appalling."

MacAskill said: "The unfortunate reality is that we simply don't have an endless supply of money.

"The courts proposed for closure account for only 5% of the total court business and in the majority of cases will be transferred to another nearby court."