What happened
Peter Cannon, 54, had been evicted by River Clyde Homes. In February 2020 he walked into the association’s office in Greenock and waited to be seen. When customer services adviser Lynne Robertson, 45, asked how she could help him, he produced a serrated steak knife and stabbed her in the right side of her abdomen.
She raised her hands and took a blow to the arm. The blade pierced her liver and left her scarred for life. She kicked out and shouted “Please don’t” and “Please don’t kill me”. A 71-year-old customer threw a chair at Cannon, which gave her the moment to reach a back office. The Scottish Sun reported that he had spoken about killing housing officers before the attack.
The outcome
Cannon pleaded guilty to attempted murder. On 27 July 2020 at the High Court in Glasgow, Judge Buchanan imposed an Order for Lifelong Restriction with a punishment part of four years and ten months. He called it “a brutal and premeditated attack with a knife upon your entirely innocent and defenceless victim”, and said “it is only by the greatest good fortune that she did not die”. Cannon had a 2002 conviction for possessing a bladed article.
What went wrong
The desk was a public counter in an open office, worked by one person, with no barrier recorded between her and the man in front of her. No source describes a screen, a panic alarm, or a colleague whose job was to watch the waiting area.
The attacker was not a stranger in the building. He was a former tenant with a long-standing grievance against his landlord, and the judge called the attack premeditated. A counter that serves the public will meet the people who are angry with it.
The escape worked because a member of the public threw a chair, and because there was a back office to run to. Robertson’s own part was to kick out and keep shouting.
What it teaches
Design the counter for the person who arrives angry. A barrier is the distance that decides whether a knife reaches an abdomen or a forearm, and it costs nothing in courtesy. Add an alarm the person at the desk can reach without standing up, and a back route that is unlocked throughout opening hours.
A known complainant is an intelligence item. An eviction, a complaint history, earlier threats and a bladed article conviction are all recorded somewhere. The record has to reach the desk before the man does.
And single staffing is the thing to fix. If you are alone at a public desk, the plan cannot rest on you noticing the danger in time.
Questions for the room
- Where is the panic alarm at your front counter, and when was it last tested?
- If a known complainant walks in, who knows before he reaches the desk?
- Is the route from your desk to a secure room clear, unlocked and walked through this month?
Evidence and limits
Confidence: confirmed. Three sources were read in full: the Scottish Sun report, the sentencing statement in HMA v Peter Cannon published by the Judiciary of Scotland, and Inside Housing. They agree on the attack, the plea and the sentence. No source records a panic alarm at the counter, so this page does not claim one was fitted. The record dates the attack to February 2020; the pack gives no date.
Our lone working training covers public-facing counters, single staffing and the controls that go with them.
Sources
- The Scottish Sun, 2020 · https://www.thescottishsun.co.uk/news/5860179/scots-housing-officer-tenant-stabbed-murder-bid/
- Judiciary of Scotland, HMA v Peter Cannon, 27 July 2020 · https://judiciary.scot/home/sentences-judgments/sentences-and-opinions/2020/07/27/hma-v-peter-cannon
- Inside Housing, 2020 · https://www.insidehousing.co.uk/news/man-jailed-for-life-after-stabbing-housing-association-worker-67298
Reviewed 20 October 2026.