The referee on duty at Hillsborough on the day of the disaster in 1989 has claimed his statement was changed to support allegations fans were drunk.
ITV documentary Hillsborough: Smears, Survivors and the Search for Truth will reveal the statement of referee Ray Lewis was allegedly changed to describe fans as drunk.
The show, due to be aired on tonight, features journalist Peter Marshall examining some of the evidence behind the stories of the disaster, in which 96 football fans died.
In April this year an inquests jury found the 96 victims were unlawfully killed and fans were not to blame.
Mr Lewis, the referee on the pitch on April 15 1989, said he had described 'mixed' groups of fans in his statement, but when he later saw a typed version of it he realised the word had been changed.
He told the programme: "When I received the typed-up version it said these spectators were pissed. So they changed the word 'mixed' to 'pissed'.
"The handwriting I must admit from the police superintendent isn't particularly good but I'm sure that anyone who would actually look at that would identify the word is definitely not 'pissed'.
"So I just feel it's been placed in there to give support possibly to police actions."
The programme will also reveal that former Premier League chairman Sir Dave Richards included allegations of bad behaviour of fans in his statement about the tragedy.
In his statement, Sir Dave, who went on to become chairman of Sheffield Wednesday after the disaster at the club's stadium, described fans shouting lewd comments about a female casualty whose blouse had become unbuttoned.
The allegations were also reported in The Sun newspaper.
Programme makers, who say Sir Dave's description of the apparently dead woman does not match any of the seven women killed in the tragedy, said when they wrote to ask him about his statement their letters were returned unopened.
The programme's investigations revealed a witness who reported the same allegations to police was the daughter of a South Yorkshire Police chief inspector who had been on duty at the FA Cup semi-final.
Cherry Daniels, whose father is retired officer David Sumner, told programme makers she informed investigating force West Midlands Police about her father's position but was told it was not relevant.
Two investigations into the disaster, Operation Resolve and the Independent Police Complaints Commission IPCC inquiry, are due to hand files to the Crown Prosecution Service at the turn of the year.
Hillsborough: Smears, Survivors and the Search for Truth will be shown at 10.40pm on Monday, December 12, on ITV.
More from The Star
Police called out to mass disturbance involving 30 people on Sheffield street
Tributesflood in for Sheffield boy Kasabian Newton Smith who 'touched the hearts of millions'
Brave woman waives anonymity to speak out about Sheffield sex attacker
Taxis 'coming under daily attack' from yobs lobbing bricks in Sheffield
Sheffield teenager jailed for life after killing friend who started a relationship with his mother
JOY TO THE WARD: Sick Sheffield children's dreams of white Christmas also turned gold and blue with VIP visits