A MISCONDUCT in public office accusation has been made against Scotland's auditor general over a contentious report which led to boats branded 'useless' being retained on a cancellation-plagued ferry service.

The Scottish Government scrapped plans to reintroduce car ferries on the Gourock-Dunoon crossing on value for money grounds, following the publication of cost estimates which are disputed by its own transport department.

Now Audit Scotland boss Caroline Gardner — who quoted figures of up to £60m for two new ships — is facing demands for an investigation into her handling of the report amid official 'concerns' over its accuracy.

Connectivity minister Paul Wheelhouse decided to keep faith with the two current lightweight, and breakdown and weather prone, passenger-only vessels following publication of the 'Transport Scotland's Ferry Services' document.

However, campaigners fighting to rid the route of the unreliable craft have seized on a comment given to the Greenock Telegraph by Transport Scotland in June, which they say amounts to 'prima facie evidence' of misconduct.

A spokesman for Transport Scotland had said at the time: "We share the concerns of others over the accuracy of cost data assumed in Audit Scotland's own report — something we raised directly with Audit Scotland at the time their report was published."

Two top Transport Scotland ferries unit officials, Graham Laidlaw and Richard Hadfield, were part of an advisory group whose expertise was sought by Audit Scotland's Ms Gardner prior to publication of her report.

But the figures of £25m to £30m for each of two new car ferries — which was given to a Holyrood MSPs committee by former Caledonian MacBrayne boss Martin Dorchester in 2017 — were kept in the Audit Scotland document.

In a letter to Ms Gardner, Susanna Rice, convener of the Dunoon-Gourock Ferry Action Group, says: "They [Mr Laidlaw and Mr Hadfield] will have been given copies of the draft report before its publication to help verify its accuracy.

"These are experienced officers who would have notified Audit Scotland of their concerns before the publication of your report.

"Their concerns must have been ignored by officers of Audit Scotland.

"This is prima facie evidence of misconduct in a public office by those responsible for your report."

Mrs Rice adds: "Subsequent to the publication of the Audit Scotland report, Paul Wheelhouse met with representatives of the Dunoon-Gourock Ferry Action Group at Holyrood on January 17 2019.

"He drew attention to the recommendations in the Audit Scotland report as justification for his decision to abandon the Gourock-Dunoon tender on 'value for money' grounds."

A £50,000 expert study commissioned by the Scottish Government in 2013 found that ships of at least 40 metres in length were needed to cope with changing weather conditions on the route and would cost £6m each for vehicle-carrying vessels.

Caledonian Maritime Assets Ltd [CMAL] says the current 'ballpark' figure for ferries capable of carrying 220 passengers and 40 cars is £10m each.

Prior to the Audit Scotland report being published it had been the 'wish' of the government to return robust vehicle-carrying ferries to the route.

Since its publication, Transport Scotland says it is committed only to maintaining a passenger-only service.

The current vessels operated by Caledonian MacBrayne have suffered thousands of cancelled sailings due to breakdowns and because they can't cope with windy weather.

The ferry action group has previously described the boats, MVs Argyll Flyer and Ali Cat, as 'useless' for the route and previous government ministers declared them 'not fit for purpose'.

The campaigners are demanding no further delay in implementing the recommendation for 40-metre long ships, arguing that vessels of this size must be able to provide a vehicle service to make them economically viable and provide a return to the public purse for the cost of building them.

Audit Scotland said earlier this month: "The content and conclusions of the [Transport Scotland's Ferry Services] report are the sole responsibility of the Auditor General."

The scrutiny body yesterday refused to comment on the misconduct in public office accusation.

A spokesperson said: "Once we have considered the letter, we will respond to the Dunoon-Gourock Ferry Action Group in due course."