Citizens Advice Scotland has appointed Derek Mitchell as its chief executive, more than a year after the previous chief executive, Margaret Lynch, was sacked after an investigation.

Mitchell, who is currently chief officer for migration, population and diversity at the Scottish local government umbrella body Cosla, is due to take up the role on 28 August.

Rory Mair, who was appointed chair of CAS in March this year, was chief executive of Cosla between 2012 and 2015 and was part of the three-strong team of board members who appointed Mitchell.

A spokesman for CAS said the recruitment process had been a “robust and competitive” one facilitated by an external recruitment process and the committee had been unanimous in its selection of Mitchell as the best candidate.

Before joining Cosla in 2005, Mitchell worked for the Scottish government as a policy adviser in the homelessness team and has previously worked in local government in a variety of management and public policy positions focusing on housing, homelessness and social work.

The CAS spokesman declined to say how much Mitchell would be paid.

Mitchell’s appointment comes after a turbulent two years for the charity, which is the umbrella body for all Citizens Advice bureaux in Scotland.

In August 2015, the charity suspended Margaret Lynch pending an investigation and she was dismissed the following March.

The same month in which Lynch was dismissed, the Department for Business, Innovation and Skills reportedly ordered the charity to carry out a governance review, withholding half the annual funding it provided to CAS to ensure the charity complied.

The review, carried out by the accounting firm Deloitte, was highly critical and recommended radical reforms to the charity and its governance. Dominic Notarangelo, chair at the time, left the charity shortly before the report was published, having been warned it would contain direct criticisms of the board’s leadership.

The reforms recommended in the report were voted in by the membership in January. The vote had been postponed when four member bureaux took last-minute legal action to prevent it going ahead.

Anne Lavery, the charity’s chief operating officer, who has been acting chief executive since Lynch’s departure, will continue in the role until Mitchell joins the charity.

In a statement, Mair said Mitchell was “ideally qualified” to lead CAS.

He said: “He is an experienced manager, practitioner and policymaker, and is strongly committed to the ethos of the Citizens Advice network, bringing a strong set of values based on social justice and public service to the position.

“He is also very experienced in managing complex stakeholder relationships and is well-known and respected within government and the sectors we engage with.”

Mitchell said he was excited to have the chance to contribute to the work of the Citizens Advice network.

“I am looking forward to working with the CAS board to ensure the organisation and the member bureaux can build on their strongest assets: their staff and volunteers,” he said.

“Refreshing, renewing and emboldening this relationship with citizens, CABs and partners will be at the heart of my agenda as chief executive.”