Spending watchdogs have unearthed significant weaknesses in a trio of public sector IT projects which cost over £130m.

Audit Scotland's probe looked into a series of delayed, cancelled or otherwise overly costly ICT projects. Caroline Gardner, Auditor General for Scotland, said their report exposed 'significant weaknesses in how they were planned, managed and overseen'.

The body also said there was a 'failure to appreciate the complexity of the programmes' and that the organisations concerned did not have sufficient specialist knowledge.

Those probed included the Crown Office and Procurator Fiscal Service (COPFS), Registers of Scotland and Disclosure Scotland.

The three projects examined by Audit Scotland had £133.3m spent on them. Its report said: 'A key factor in the failure to deliver the programmes as intended was the public sector bodies' lack of specialist skills and experience. This contributed to a lack of understanding about the complexity of the programmes and an over-reliance on the supplier for key decisions affecting the design and implementation of the necessary technology.'

Disclosure Scotland spent £19m on its Protecting Vulnerable Groups programme, including a new ICT system to check and issue disclosure certificates. The report said the programme 'experienced a number of significant problems' and is now expected to be delivered 18 months late.

Registers of Scotland, meanwhile, shelled out £112m - despite the original cost being estimated at £66m - having reached an agreement with BT in 2004 for ongoing ICT provision and updates to its IT systems. It has now given notice to end the contract 20 months early.

COPFS shelled out £2.3m on a new programme to upgrade its case management system. Costed at £10m, the project was mothballed in November 2010 due to increased costs and a fall in the organisation's budget.