At 62, Haughey, a native of Co Louth, has built a fortune worth in excess of 400m from his veterinary pharmaceutical business, Norbrook Laboratories. In 2004 the firm reported turnover of roughly 120m and pre-tax profits of almost 13m.

His legal battles have even extended to his former housekeeper. In 2003, Linda Heaton was awarded 10,500 for unfair dismissal. She claimed at the employment tribunal that Haughey had "bellowed" orders and engaged in "stroppy" behaviour that left the home help on "tenterhooks".

The tribunal concluded that Haughey "liked things done his own way" and "occasionally raised his voice when he was displeased", but it rejected Heaton's claims of bullying.

Some other employees have taken decidedly drastic action. A cowhand at Haughey's estate in Northern Ireland once chased him around the grounds with a pitchfork following a dispute about a colleague. Two RUC officers passing by were alerted to the commotion and arrested the cowhand. Haughey was treated in hospital for a cut.

Nominated to the Seanad by Albert Reynolds in 1994 and by Bertie Ahern in 1997, Haughey now prefers to be known as Lord Ballyedmond.

He has Tory inclinations, and has donated over 1.4m to the Conservative party's 2001 election campaign. Three years later, he was made a peer.

He has previously attributed his success to the "contradictions" in his character.

He described himself as "both militant and moderate, idealistic and realistic" when Norbrook received an enterprise award in 2002.

In recent times, Haughey has been flexing his legal muscle, not only against the Commission for Energy Regulation, but against locals living close to a Norbrook Laboratories site in Great Corby. Haughey lives in the 1,000-acre Corby Castle estate, close to Carlisle in the north of England.

Last month his solicitors issued a writ against a former chairman of a parish council, claiming aggravated damages for libel on behalf of Haughey and Norbrook Laboratories. The company employs over 100 people in Carlisle, with another 1,000 working for Norbrook in Northern Ireland.

The writ was issued against Nigel Holmes after anonymous letters were circulated in Great Corby apparently suggesting that locals should object to a planning application to create parking spaces next to a pub in the town.

Norbrook Laboratories has applied to create a restaurant at the pub in question and wants seven spaces for parking.

The letter could be signed by locals and sent to the council to object to the plan. Some locals who did sign were also contacted by Norbrook Laboratories' solicitors. The solicitors claimed locals had been misled into signing what it described as a "defamatory" circular.

Should Haughey wish to calm his nerves away from that fray, he can always leave via Carlisle airport to retreat to Northern Ireland. Haughey bought the airport in 2001 from the local council. But even in his native land, things are not necessarily easy.

Last year, Haughey lost a legal battle when he sought title to a derelict cottage and garden next to his estate in County Down.

He claimed the property under a law called adverse possession, which enables someone to gain possession of property after 12 years if they can prove they exercised control and custody over it during that period. It was estimated that the site in question, with views over Carlingford Lough, was worth over 400,000.

Guy Scott-Foxwell was brought up in the cottage and claimed he had rights to the property.

The judge hearing the case said it was clear that Haughey's two firms, Norbrook Laboratories and Ballyedmond Castle Farms, had a firm intention to possess the disputed land and had been in factual possession of it. However, he added that Haughey's firms had failed to show they had rights to the property, and he gave Scott-Foxwell possession of it.

"It was a classical case of the little man against the big industrialist and the attendant financial risks involved, " said Scott-Foxwell's solicitor at the time.

"It is gratifying to know that at the end of the day justice has been done."