There are four main theories explaining poltergeist phenomena

Religious - the belief that the activity is being caused by an unclean spirit or demon that has entered the victim. Fundamentalist Christians believe that this invasion is more frequent than we would think, and contrary to popular religious reports, exorcisms and prayer meetings to cast out unwanted demons are common place. Perhaps not as dramatic as portrayed in some films, but nonetheless, they do take place. Devil worship is usually cited as a cause, but according to the church, this activity is much rarer than the tabloids would have us believe. What is commonplace, is the misuse of so called occult practises - astrology, Ouija boards, séances, divining etc. - they are all gateways for demonic entry.

Four stages of manifestation have been identified by the church. The first stage is Infestation, where the entity or demon seems to move things around at random. The second manifestation is Oppression where the entity or demon is in a position to affect the well being of the victim, spiritually, physically and mentally. The third stage is Possession, where the demon or entity takes control of the victim, fighting for It’s hidden agenda, commonly assumed to be the possession of the soul, but not necessarily so. The fourth, and final manifestation is Death.

Spiritual - the belief that the activity is caused by the spirit of a deceased person or ‘lower entity’ that has not moved on to the next plane of existence, has not ‘passed into the light’. The activity is attributed to anger or frustration on behalf of the spirit at not being able to come to terms with a violent or sudden death, or at not being able to communicate with the family or persons under siege for instance. ‘Lower entities’ or demons can also inhabit the other dimensions where spirits are believed to exist, and can also contribute to poltergeist activity. Mediums are used to ‘persuade’ the spirits to move onto the next plane of existence, or to simply leave the victims alone. In the case of serious demonic possession, spiritualist will seek an exorcism.

Whilst Spiritualism and Christianity may seem like they occupy the same theological ground, Christian doctrine is very specific about the fact the communing or claiming to commune with the dead or spirits is not divine, and therefore the work of the devil. The Bible states that anything claiming to be spiritual that is not God, or a messenger of God, is unclean and evil. Use of Ouija boards, séances and clairvoyancy, widely practised and used in the Spiritual movement, is strictly forbidden in Christian religions. Spiritualists are more tolerant of their differences with Christians. Other variations on the spiritual theme include voodoo, witch doctor curses etc.

Scientific - the belief that the activity is entirely caused by some natural mechanism of the mind, as yet unexplained by science - commonly referred to as Psychokenesis (PK), the ability to move objects with the mind. Telepathy, the ability to see or hear things with the mind, is also claimed to explain hearing voices or sounds in an alleged haunted house. Whilst the scientific explanation is attractive in this technological day and age, there is no real evidence, although the theory is awash with almost overwhelming circumstantial evidence. Most scientific investigations have been carried out by very dedicated amateurs whose techniques and practises are far from a laboratory environment. The common conditions for poltergeist infestation, presence of pubescent girls, recent family trauma for instance, are commonly hijacked by PK investigators as proof of some kind of psychological trigger for PK - it should be noted that these conditions could also be regarded as a clear gateway for demonic infestation.

Various conspiracy theories have included top secret government agencies using PK to carry out political assassinations, effect government and elections, convening with beings from another planet etc. The connections with these kinds of groups often invalidates the claims of so called scientific investigations.

Fraud - in the cold light of day, this is perhaps the most tangible explanation. Religious and Spiritual theories rely heavily on belief, citing evidence that is extremely circumstantial or pure philosophical presumption. The scientific data is equally shaky, there is a noticeable lack of photographic, electronic or audio evidence. What evidence does appear, tends to support the theory for fraud even more. Sensational cases such as the Amityville Horror and the Smurl Poltergeist have all been connected with book and movie deals, often netting the alleged victims, thousands. It cannot be denied that most cases are probably fraudulent. Some cases appear to started as a genuine infestation, but turned into fraud once the spirits were expected to perform for the media, the Enfield Poltergeist being a prime example.

However, there are some cases where there are credible witnesses and no apparent gain for the victims, indeed, genuine suffering. No matter how few or far between, in those instances, one must look to the three other explanations, or indeed other theories, for a solution.

In late August of 1977, Mrs Peggy Harper, a divorcee in her mid forties, had put two of her four children to bed. They were living in a semi detached council house in Enfield, North London that had three bedrooms. Late at night, Janet, aged eleven and her brother Pete, aged ten, complained that their beds were "jolting up and down and going all funny". As soon as Mrs Harper got to the room the movements had stopped - as far as she was concerned her kids were making it all up.

The following night at 9.30 pm, Peggy was called to Janet and Pete’s room when they complained something was making a shuffling noise. Janet said it sounded like one of the chairs moving, so Peggy took the chair out of the bedroom to put their minds at ease. Saying goodnight to the children once more and turning off the light, she too heard the shuffling noise. As though somebody was "shuffling across the floor in their slippers". She turned the light on to see the furniture as normal and the children under their covers. Turning the lights off again, the noise started once more.

They then heard four loud knocks on the partitioning wall of the house and Mrs Harper was astonished to see a heavy chest of draws moving about 18 inches across the floor, well beyond the childrens reach. As soon as it stopped, Mrs Harper pushed it back against the wall but as she turned her back, it moved once more to it’s former position. This time she found it impossible to move. Mrs Harper recalls shaking with fear, yelling at the children to get out of their beds and to go downstairs - she was convinced that something unexplainable was going on. Seeing that their neighbours lights were on, the Harpers, still in their night clothes, ran next door for help.

The neighbours searched the house and garden but found no-one. Soon they also heard the knocks on the walls which continued at spaced out intervals. At 11pm they called the police, who heard the knocks, one officer even saw a chair inexplicably move across the floor, and later signed a written statement to confirm the events.

The following day, the events continued with small plastic bricks and marbles being hurled around house - when picked up, they were found to be hot. This ‘attack’ continued for three days by which time they sought help again, not only from the police, but a local vicar and local medium. But no-one seemed to be able to stop the escalation of events. The Harpers eventually turned to the press and the Daily Mirror sent out a reporter, Douglas Bence, with a photographer, Graham Morris, who stayed in the house for several hours. Nothing happened and the reporters decided to leave - they were almost in their car when the ‘flying bricks’ promptly resumed. They were called back and a toy lego brick flew across the room hitting the photographer on the forehead as he attempted to take a picture. Later, as the photographer developed his negative he noticed that it had an inexplicable hole in it and that the flying brick could not be seen. Senior reporter at the Daily Mail, George Fallows, was so impressed by his colleagues experience that he followed up the story himself. He suggested that the Harpers call in the SPR (Society for Psychical Research) which in turn contacted Maurice Grosse, a member and resident of North London.

Grosse arrived at the Harpers on September 5th, a week after the disturbances had begun. For the next few days nothing out of the ordinary occurred. Then, on September 8th, whilst Grosse and a journalists from the Daily Mirror were keeping vigil, between 10 pm and 11 pm, they heard a crash in Janet’s bedroom. They discovered that her bedside chair had been thrown about four feet across the room where it was lying on it’s side. Janet was asleep at the time and no one saw the chair move. But when it happened an hour later, the photographer Morris was ready and captured the event on film.

Grosse claims that then he experienced the strange happenings - rirst a marble was thrown at him from an unseen hand, he saw doors open and close by themselves, and claimed to feel a sudden breeze that seemed to move up from his feet to his head.

On 10th September, the Enfield case made the front page of the Daily Mirror, then the story was picked up by LBC radio ( a London based station) and that evening, Grosse, Mrs Harper and her neighbour took part in a two and a half hour NIGHT LINE programme.

The phenomena continued - there was interference with electrical systems in the house, electrical faults and mechanical equipment failure, as soon as camera flashes were recharged they were quickly drained of power, an infra red sensitive television camera was brought in to do remote monitoring of the bedroom, but as soon as it began filming the tape would. The same thing happening to the BBC Radio reporters tapes when tape cassettes were found to be damaged, often the recordings erased, the metal inside some of the machines would be found bent, and even some of the tape decks would disappear reappearing several hours later.

Grosse was soon joined in his investigation by writer Guy Lyon Playfair and the two men spent the next two years studying the case until it finally ceased.

The knocking on walls and floors became an almost nightly occurrence, furniture slid across the floor and was thrown down the stairs, drawers were wrenched out of dressing tables. Toys and other objects would fly across the room, bedclothes would be pulled off, water was found in mysterious puddles on the floors, there were outbreaks of fire followed by their inexplicable extinguishing, curtains blowing and twisting in the wind when all windows and doors were closed, even accounts of human levitation - Janet claimed to have been picked up and flung about her room by an unseen entity (witnessed by neighbours passing by and looking up into the girls’ bedroom). Both girls claimed that they were being pulled out of their beds by an invisible force and Janet claimed that the curtain beside her bed twisted several times in a tight spiral and attempted to wrap itself around her neck trying to strangle her. This was backed up by her mother who had witnessed this more than once.

Soon an extraordinary harsh rough male voice was heard - coming from Janet’s throat. Janet claimed to have no control over the voice, and would even appear to be in a ‘trance’ like state when the voice occurred. The voice claimed to be several identities, often speaking in obscene language. One character who did keep reappearing was ‘Bill’ who claimed to have died in the house. Out of all the voices, this was the only one that could be verified. ‘Bill’ was a man who had allegedly died in the house, and event that none of the Harpers knew about.

Psychiatrists and local doctors were brought in to see whether this was indeed Janet being mischievous or if a second personality was developing, or perhaps there was indeed a paranormal ‘entity’. Maurice Grosse spoke to speech therapists who suspected that the voice was not coming from Janet’s usual vocal chord equipment but by the second set of vocal chords all people have. Actors can be trained to speak using these ‘false chords’ to produce a deep gravely voice, however it can be a painful process. This theory was soon backed up by a recording of ‘the voice’ on a laryngograph (registers patterns made by frequency waves as they pass through the larynx). However to keep up this ‘gravely’ voice for hours on end would naturally have consequences on Janet’s normal voice. But Janet’s voice did not seem to be affected

Grosse deemed that the source of the poltergeist activity seemed to have intelligence of some kind, since it would rap out answers to simple questions - one rap for no, and three for yes. During a session, Grosse asked how many years ago the supposed entity had lived in the house - there followed 53 raps.

Mediums were brought in to help and Janet spent six weeks in Maudsley Hopsital in South London where she underwent extensive tests for any signs of physical or mental abnormality - but none were found and during this time the poltergeist activity ceased.

Professor Hasted, head of physics at Birkbeck College, University of London, assigned his assistant to help identify the problems in the house, especially the spontaneous metal bending and snapping that appeared to be occurring around Janet.

Not everyone was as willing to believe that this was entirely paranormal activity as Grosse and Playfair seemed to be - further researchers were sent by the SPR (Society for Physical Research) - Anita Gregory and John Beloff. Gregory was convinced that all the activity stemmed from Janet’s trickery. She claimed that they were excluded from the children’s bedroom when the phenomena was said to occur and that they would hear a ‘thump and a squeal’ from Janet’s room and upon entering they would find Janet sitting in the middle of the floor claiming she had been flung there by the ‘entity’. Another occasion, Gregory was allowed into the room but had to stand with her head towards the door to allow the poltergeist activity to occur - it proceeded by throwing objects at her head whilst she heard the children giggling. Gregory believed the voices to be muffled voices of Janet and her thirteen year old sister Rose covering their mouths with their bedsheets or averting their faces whilst producing this ‘phenomenon’. During her visit, Gregory ‘caught’ Janet cheating - a video camera had been set up in a room next door to Janet that recorded her bending spoons and attempting to bend an iron bar by sheer force, as well as "bouncing up and down on her bed, making flapping movements with her hands". Janet admits to having done this. She claims that she "wanted to see if the investigators would catch her out - they always did".

Gregory also claims that Janet’s Uncle, John Burcombe had told her that he believed that Janet had taught herself to talk in a deep voice and that she had always been a mischievous child, enjoying misleading strangers. Janet was also an athletic girl who could have quite easily jumped from her bed to the floor when she claimed she was being ‘thrown’ by the ‘entity’.

After two years, the events subsided and the Harper family continued their normal lives.

Was this genuine phenomena? If not, why did the Harpers have their household disrupted for two years, invaded by investigators, psychiatrists, mediums? Because the Harpers went to the newspapers in the very beginning, sceptics argue this was a hoax. Did Maurice Grosse, the paranormal investigator, who had lost his young daughter Janet in a car accident only a year earlier, want to believe too easily in the paranormal? Was the Poltergeist activity caused by frustrations externalising? Some researchers believe that sexual frustration can aid the activity - such as Janet beginning menstruation and her mother going through the menopause? Was the recent divorce of Janet’s parents a contributing factor? Two years later, why did the activity mysteriously stop? It was also claimed that Mrs Harper was trying to get to the top of the housing queue as it was becoming quite common for council tenants to have created ‘haunted houses’ - however Mrs Harper refused to leave her home.

It is widely believed that this case began with genuine phenomena, but soon turned to trickery. As the media demanded paranormal activity, eleven year old Janet and thirteen year old Rose, were not going to allow them to go away disappointed, and revelled in the attention.

Photo Strip above - in the photo strip pictures above, the curtain by Janets Bed mysteriously wraps itself around her bed sheets and attempts to pull them off.