Not just ‘part of the job’: Man sentenced for knife attack on officers

It is never acceptable to assume assaults on police officers are just ‘part of the job’.

That’s the message from one of our senior officers after an attacker armed with a knife seriously injured a policewoman in the line of duty.

Declan Diedrick left one officer with an injury to her face which required urgent hospital treatment in an attack in Harlow on 29 December 2023.

We received calls with concerns for the safety of Diedrick, 25, of no fixed abode, in Hull Grove on the evening of the incident, before the first two officers at the scene were made aware he was also in possession of the seven-inch serrated kitchen knife.

When they tried to get him to put it down, an altercation with the officers began and Diedrick stabbed one of them before being handcuffed on the floor as more officers arrived and a member of the public intervened.

Diedrick admitted wounding without intent and possession of bladed article in a public place at an earlier court hearing, however prosecution proceeded with trial where he denied further charges against him – he was found guilty of causing grievous bodily harm with intent by a jury at Chelmsford Crown Court on 30 October 2025.

On 8 December at the same court, he was sentenced to five years in prison, with an additional three years on licence.

Speaking after the hearing, Superintendent Tony Atkin commended the officers who responded on the evening of the attack:

Everyday officers across Essex willingly go towards danger in order to keep the public safe. We are honoured to help those in need and stop those harming others.
This incident shows the best of our officers and the dangers they face; our officers were at the scene within minutes of receiving a call for help, and then faced Diedrick as he repeatedly tried to attack them with a knife.
From arriving at the scene to arresting Diedrick, there was less than 60 seconds. This highlights the professionalism and effectiveness of those on scene, and shockingly, how quickly he could have injured them further.
Diedrick had a clear intent and determination to harm those officers and the violence he showed that night was truly horrifying.
The first two officers on the scene were subject to a savage attack, with one sustaining a serious stab wound to the face.
Despite everything those officers went through they remain in frontline policing duties and continue to help the people of Harlow.
This exemplifies the incredible bravery of all our officers, trying to do the best for the people they serve.
All too frequently our officers face violence and it is never acceptable to assume assaults on police officers are just ‘part of the job’.
Police officers are members of the community, and an attack on one of our officers is an attack on our community and will not be tolerated
Policing is often tough, with officers regularly in very challenging situations. These incidents not only directly affect the officers, but their family and friends too.
It is completely unacceptable our officers and staff were assaulted almost 1,300 times last year – that’s more than three times a day. As today shows, if anyone crosses that line, we will not hesitate to take robust action.
I’d like to end with a thank you to all those in Essex Police and the Crown Prosecution Service who helped secure this sentence against Diedrick, as well as the members of the public who assisted us on the night of the attack in December 2023.
All their work has seen justice served.

In a statement the injured officer PC Hollie Matthews provided to the court, she said:

Policing is made up of real people, with families, with friends and with a life. I know I speak for myself and many others when I say I joined the police to be part of something that helps, something that supports, someone who runs towards the danger when everyone else runs away.
This incident is one I have thought about everyday, often for hours on end, over and over.
In moments like this in this job you don’t consider yourself to be anything other than a police officer – you do what is right and for me was stopping him from harming himself or others.
However, the reality is under my uniform I am a person, a person with feelings, a person who is a human being, a person who is now a victim.
The police are who you call in the worst moments of your life, yet I have been called to one of the worst of mine.

Chair of Essex Police Federation, Steve Martin, said:

I am pleased to see the judge has delivered a sentence that reflects the seriousness of this violent offence. It sends a clear message that assaults against police officers will not be tolerated.
Despite the severity of the assault our officers demonstrated exceptional courage and professionalism, successfully restraining the individual and preventing further harm. Their actions reflect the highest standards of policing and public service and I am immensely proud of them.
Having viewed the footage of the incident which shows the terrifying nature of the attack, it is difficult to comprehend the fear and danger the officers faced. Diedrick continued his attack even after a brave member of the public intervened - an act of heroism that prevented an even more tragic outcome, for which I thank him.
These first responding officers are a credit to Essex Police. Their bravery and resilience in the face of such violence deserves recognition. I extend my deepest admiration and support to them as they continue their recovery and return to duty.
This incident serves as a stark reminder of the dangers officers face daily.

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