The vulnerable victim was used and exploited during that period by his “boss” Peter Swailes Senior at the various “accommodations”.
Swailes Senior, 80, who died last year while awaiting trial for the modern slavery offences, approached the man when he was aged about 18 and invited him to work with him doing various jobs.
In October 2018, following a tip-off, the man was discovered by police living in a shed with no heating, no lighting and no flooring on a residential site near Carlisle, Cumbria.
In contrast Swailes Senior lived in comfort in an adjacent chalet filled with expensive belongings, while the family dog slept in a similar-sized shed that contained a fitted carpet and a gas heater.
On Friday, his son, Peter Swailes Junior, 56, received a suspended jail sentence after he admitted conspiring with his father to financially exploit the man from July 2015 – when the Modern Slavery Act came into law.
The Crown accepted Swailes Jnr’s basis of plea that although he had known the victim for many years he was unaware of his living conditions.
Swailes Jr, of Low Harker, Carlisle, accepted that from “time to time” his father would contact him and arrange for the victim to undertake work with him, and that “on occasion” he paid him less than his minimum entitlement.
Opening the case, Barbara Webster, said: “He (the victim) was found by the police living in a rotten shed, with water pouring through it, with a make-shift bed, and congealed vomit in the corner. Not the way that anyone would choose freely to live and not where he would be if he could have found himself better living accommodation.
“He had few possessions to show for his 40 years’ hard work. He only had a wash bag, three second-hand coats, a few stained duvets, and CDs.”
He lived with the Swailes family for many years after being in care as a child, with Swailes Snr telling him he was his “boss”, Ms Webster said.
When not undergoing dangerous work such as repointing chimneys and replacing roof tiles, Swailes Snr would order him to do chores such as painting the kitchen and cutting the grass.
Ms Webster said: “Peter Swailes Senior had a far better standard of living – an elaborate, carpeted home with expensive personal belongings. A palace, by contrast to where (the victim) lived.”
When officers attended the traveller site in October 2018, the victim told them he only received £10 a day for his work duties.
The court heard Swailes Jr had left the family home aged 14 in fear of his father.
Judith McCullough, defending, said he and his father had not worked together and maintained separate businesses.
She said: “Peter Swailes is coming to terms with the fact that on occasion he undermined the trust and affection.
“He would employ (the victim) on a casual basis and on occasion he paid less than he ought to have done.
“For that he is sorry.
“He was shocked and angered to see the full picture once these proceedings were under way.”
Judge Richard Archer told Swailes Jr: “You may not have known the true extent of (the victim’s) living conditions, or his precise IQ, but it must have been obvious to you that he did not have any real appreciation for the potential consequences of some of the work that you required him to perform at an undervalue and with little or no regard for his personal safety.”
Sentencing the father-of-five to a nine-month jail term, suspended for 18 months, he said he took into account a pre-sentence report, which assessed Swailes Jr as posing a “very low” risk of reoffending, and also his personal mitigation, including his poor health.
The charges came following a three-year investigation by the Gangmasters and Labour Abuse Authority (GLAA), supported by Cumbria Police and the National Crime Agency.
The victim, aged in his 60s, now lives in supported accommodation outside of Cumbria and has been helped by City Hearts, a charity providing long-term support to survivors of modern slavery.
He said: “I was kept in a padlocked shed on a mattress, unable to leave unless I was told I could.
“I didn’t run away because I had nowhere else to go.
“I now go on daily walks just because I can. I enjoy long walks to the shops, watching football and have made new friends.”