NORTHUMBRIA’S chief constable has announced her retirement after 30 years of service – weeks after it was revealed she was being investigated following complaints of discourtesy toward her colleagues.

Sue Sim joined Merseyside Police in 1985 as a graduate entrant, progressing through the ranks in both uniform and CID roles.

She came to Northumbria in 2004 as an assistant chief constable and was promoted to deputy chief constable in 2008.

Traditionally, a senior officer can only hold two chief officer posts in one force.

However, the Police Authority were so determined to keep Mrs Sim in the force that they took the unprecedented step to ask the Home Secretary for special permission to allow her to apply for the position of chief.

When she was appointed in 2011 she was the first woman to lead a Metropolitan force.

She also lead the Association of Chief Police Officers’ public order portfolio for a number of years, where she provided strategic advice at a national level.

Mrs Sim was honoured with the Queen’s Police Medal in 2009 and became Deputy Lord Lieutenant of Tyne and Wear in 2014.

She said: “I have always been warmly welcomed by the public here.

“They are incredibly supportive of their local police and we could not achieve the success we do without them.”

This was particularly evident during the search for Raoul Moat following the murder of Christopher Brown and shooting of one of her own officers, PC David Rathband.

Mrs Sim said: “That was one of the most challenging times of my career and the largest manhunt the country has seen for 44 years.

“I spent my time out and about reassuring the public and responding to their questions. “Despite their concerns they never waned in their support for us and I am immensely proud of my officers and staff who went about their roles fully aware of the threats against them, but determined to support the public.”

Explaining her decision to retire now, she said: “After careful consideration I have decided to retire when I reach my 30 years service on 3rd June.

“My family have made many sacrifices to enable me to have such a fantastic career and it is now time to spend more time with them.

“I am obviously sad to leave but it is the right time and I am confident I have left a legacy of high performance that will continue.”

In a statement released this afternoon, Northumbria Police and Crime Commissioner Vera Baird said: "Chief Constable Sue Sim gave me formal notice of her decision to retire on Wednesday April 8 and she will leave the force on June 3 when she has completed 30 years of public service in policing.

"Sue has brought passion and enthusiasm to her role with Northumbria Police, always remaining focused on cutting crime and ensuring victims of crime are at the heart of everything Northumbria Police does.

“She leaves at a time when Northumbria is one of the highest performing forces in the country and the best force of all for the important matter of victim satisfaction.”

Ms Baird added: "She and I have worked well together over the two-and-half years since I became Police and Crime Commissioner.

“She responded to the challenge of this new governance structure very positively and my experience of her is that she always, without exception, delivers what she has promised. “She helped me to deliver a strategy to ensure Northumbria Police was recognised as a national leader in tackling violence against women and girls and she has revolutionised the way police officers engage with communities.

"She has played a key role in the success of this force overall, and she has been supported by the excellent officers and staff in Northumbria Police.

"With her team, she has worked hard to meet the challenge of a reduction of 37 per cent from our budget.

“She was determined to protect neighbourhood policing in the public interest and she has succeeded.

"I will miss our joint working and I wish her well in her retirement."