A 91-year-old dad died after weeks of suffering and shocking neglect by his own son.
Edward Hedley had life threatening bed sores which gave off an aroma of "rotting flesh" and slept in a home that reeked of urine.
Two of his sores were "eaten through to the bone".
The pensioner would be found in a confused and cold state, roaming the streets in the dark and not even knowing his own name.
In the last fortnight before he was finally admitted to hospital on Christmas Eve 2012, he had been virtually unable to move at all and was "emaciated".
He death on January 12 2013, after developing pneumonia, cannot be "proven as a certainty" to be linked to the neglect he had suffered in his final five to six months.
Newcastle Crown Court heard the elderly man endured the heartbreaking plight despite his son William Hedley telling social services he would be on hand for his dad 24-hours a day.
Instead of providing the sick man with constant, loving care, Hedley, who "cannot bear to be told what to do", developed an obsession with keeping away the officials who were trying to help his dad.
The 64-year-old even commenced proceedings in the county court in a bid to get an injunction to stop social services visits and forged letters in his father's name claiming his wishes were being carried out.
Hedley jnr, of Royal Crescent, Newcastle, denied neglect but was convicted by a jury of eight charges after a trial.
Judge Deborah Sherwin sentenced him to 18 months behind bars.
The judge told him: "It is unfathomable you didn't seek medical attention for your father at this point.
"During this period, the jury found, you had accepted care of him and willfully neglected him.
"The mystery is, why?
"I have no doubt of your closeness to your father but I am also satisified you are someone who cannot bear to be told what to do and have real problems with anyone you perceive to be in authority.
"You told the jury you have complained about almost everyone who you had dealings with over this.
"You also told the jury you spent increasingly long periods of time preparing for court cases you were conducting.
"I have no doubt you became so obsessed with this, not least because of the way you have conducted yourself in your defence, that you became blind to your father's suffering.
"His final months must have been miserable.
"You have shown no remorse for your actions.
"You are suffering the loss of your father but seem unable to accept how much you blighted his final weeks."
The court heard it was on December 24 2012 Hedley jnr finally called for help for his suffering dad.
Distict nurses came to the house and were "shocked" by what they saw so summoned senior assistance.
Eventually, after "debate" with Hedley,jnr he agreed an ambulance could be called.
Two of the pensioner's bedsores were life threatening and had "eaten through to the bone" - but were easily preventable.
One of the sores was described by a nurse as being the size of a fist.
Despite his hospital admission, Mr Hedley snr died, after developing pneumonia, within weeks.
The judge said the death could not be "proven as a certainty" to be linked to the neglect he had suffered.
Prosecutor Gavin Doig told the court the neglect offences related to the pensioner's personal safety, accommodation, hygiene, nutrition and medical treatment.
In July 2012 the pensioner had been found by a police officer, staggering across a field near his home in a confused state.
Mr Doig said: "He was taken home. He didn't recognise his own home, had wet
himself and within minutes had forgot who the officer was."
The court heard Hedley jnr had returned home, disputed his father needed any help and said he would put a complaint in against the police officer.
In November that year Mr Hedley snr had been found wandering at 2am in cold and wet weather conditions.
Mr Doig said; "Edward Hedley didn't know his name, his date of birth, didn't know where he was.
"Police returned him home. The defendant wasn't there."
Mr Doig said both Mr Hedley snr and his home smelt of urine and plastic bags covered the sofa where he slept as well as his mattress.
The pensioner was described as "emaciated" when he was finally taken to hospital.
Mr Doig added: "The defendant was certainly living with him, not 24 hours a day but permanently or semi-permanently.
"He refused to let any party assist him in caring for Edward Hedley.
"By allowing his condition to deteriorate to this shocking extent the neglect was to the most serious degree for an extended period."
Hedley jnr, who represented himself during the proceedings, said he believed the case against him had been "wrongly brought to court in the first place".