Independent investigation following wrongful conviction of Peter Sullivan

27 Mar 2026 04:30 PM

The Independent Office for Police Conduct (IOPC) is investigating complaints linked to the Merseyside Police investigation that led to Peter Sullivan being wrongfully convicted of murder.

We received a referral from the force on 22 January following a complaint from Mr Sullivan, who had spent 38 years in prison for the murder of Diane Sindall, in 1986.

We are speaking to several agencies involved to determine what records are available in relation to his case that may be relevant to our inquiries. We continue to gather and carefully review this material, and have spoken to Mr Sullivan about his complaint, to determine the terms of reference for our investigation.

IOPC Director Amanda Rowe said:

“Mr Sullivan was a victim of one of the worst miscarriages of justice this country has ever seen. Our thoughts are with him as he continues to rebuild his life.

“In light of the significant impact this has had, as well as the severity of some of the allegations contained in the complaint, it is important for these matters to be independently investigated.

“The fact this took place almost 40 years ago poses substantial evidential challenges, however we will do all we can to progress our inquiries as quickly as we can, while taking all appropriate steps to ensure this does not hinder the ongoing investigation by Merseyside Police into the horrific crime against Ms Sindall.”

Our investigation is separate to the force’s criminal investigation into events in 1986.

Ms Sindall had been subjected to a violent assault, and her body was found in Birkenhead in August 1986. Mr Sullivan was arrested later that year and in 1987 he was convicted of murder.

Following an application to the Criminal Cases Review Commission in 2021, a DNA profile was obtained which did not match Mr Sullivan’s.

On this basis, the Court of Appeal quashed Mr Sullivan’s conviction in May 2025.

We wrote to Merseyside Police in July 2025 about the matter. The force confirmed it had not received any complaints at that time and had not identified any potential misconduct linked to Mr Sullivan’s case. We advised the force that a referral should be made if the situation changed.

In November 2025, the BBC broadcast an interview with Mr Sullivan, in which he raised a number of concerns about the handling of the case by Merseyside Police. This formed the basis for the complaint that was referred to us in January.