[5] While serving a five-year sentence at HMP Walton, Sykes secured the opportunity to join the Maple Leaf Amateur Boxing Club in Bootle, which was overseen by a local magistrate.
This arrangement allowed him to represent the North-Western Counties team in 1973 while on a temporary release, positioning him as a potential ABA heavyweight champion.
In his sixth fight, Sykes knocked American David Wilson unconscious and continued to hit him as he draped over the ropes before the referee managed to pull him away.
After his release in 1978, he found himself in promotional photographs with Don King and Larry Holmes,[17] and also travelled to the United States to stand in as a sparring partner for Leon Spinks.
Sykes' manager, Tommy Miller, later said, "Paul could have gone right to the top, quite easily .. he impressed everybody", but "he was always in trouble one way or another, he'd always loads of worry on his mind.
"[20] His professional career ended in March 1980 when Nigerian heavyweight Ngozika Ekwelum knocked him out in the first round of a fight in Lagos, Nigeria.
Sykes committed violent offences all over Northern England and was known to locals and the police in Leeds, Liverpool, Blackpool, Hull, and Rotherham.
Referring to him as 'Sykesy', Bronson describes him as "a legend, born and bred" and writes: "I first met Sykes in Liverpool in the early 70s and at that time he was probably the fittest con in Britain.
Bronson then goes on to relate an incident said to have taken place in HMP Liverpool, when Sykes allegedly killed the prison's cat and fashioned it into a 'Davy Crockett' hat.
In 2000, Wakefield Council secured a two-year ASBO banning him from the city centre after a string of aggressive drunken incidents, including shouting abuse and urinating in public.
Paul Leighton Sykes is serving a life sentence for stabbing Michael Gallagher to death in a sudden knife attack in Lupset, Wakefield, in June 2004.
In 2008, 25-year-old Michael Sharp was given a minimum 27-year sentence at Leeds Crown Court for murdering 38-year-old David Ward, a former police officer, following a botched armed robbery at his home on Denby Dale Road in Wakefield.
[32] His death certificate states his occupation as 'author (retired)', and the funeral service was held at Wakefield Baptist Church, which he regularly attended.