The parents of Harry Dunn have lodged an official complaint against the Crown Prosecution Service (CPS) – claiming they have been left “totally in the dark” and “completely unsupported”.

Charlotte Charles and Tim Dunn have issued the complaint through their MP, Andrea Leadsom, accusing the CPS of a “serious and wholesale breach of the Victims’ Code”.

The CPS were handed the complete file of evidence in November and eventually charged 42-year-old Anne Sacoolas with causing death by dangerous driving around seven weeks later on December 20.

Mrs Charles and Mr Dunn had requested two meetings in that period, but Chief Crown Prosecutor Janine Smith told them a meeting would “not be possible”.

The PA news agency understands Ms Smith wrote to Harry’s parents in March to say the CPS were “satisfied that it has fulfilled its responsibilities under the Victims’ Code” – adding that explaining their next steps could “compromise operational effectiveness”.

Harry, 19, was killed when his motorbike crashed into a car outside a US military base in Northamptonshire in August last year.

Mrs Sacoolas, the wife of a US intelligence official based at RAF Croughton, claimed diplomatic immunity following the crash and was able to return to her home country, sparking an international controversy.

Speaking on behalf of the family, their spokesman Radd Seiger told PA: “Harry’s parents recognise and appreciate the outstanding work prosecutors do up and down the country each and every day.

“They are largely overworked and underpaid but perform a vital role in keeping the nation safe whilst bringing cases to court strictly in accordance with strict guidelines.

“Very sadly, the parents have now been left with no option but to bring a formal complaint against the Crown Prosecution Service through their MP Andrea Leadsom.”

He continued: “They are in the precise position that the Victims’ Code requires them not to be, totally in the dark and feeling completely unsupported.

“It is now nearly four months since the USA rejected the extradition request for Anne Sacoolas, yet there has not even been the slightest attempt on the part of the CPS to make contact with the parents to keep them up to date or discuss their needs.

“It is the most serious and wholesale breach of the Victims’ Code that I have come across and it is totally unacceptable, heaping further needless misery on the parents.

“Worse still, they have failed to offer any meaningful explanation for the breach despite my best attempts to politely remind them of their responsibilities.

“We know Mrs Leadsom is upset with them too. The parents had one meeting with the Director of Public Prosecutions on December 20 last year when he explained the charging decision the CPS reached. That is it.

“It is not good enough. The parents have rights and we will ensure those are met.

“The case may have its difficulties and complexities but it is for the CPS to find a way to ensure that the parents’ rights are met whilst ensuring the suspect’s right to a fair trial when she is back.”

A spokeswoman for the CPS said: “We have kept Harry Dunn’s family up to date at all stages and the Director of Public Prosecutions has met with them to explain the charging decision in person.

“We have worked to meet the Victim’s Code at all times.”