It is sometimes said that the world of IT has more wannabe and erstwhile criminals in its ranks than an average episode of the Sopranos. This article looks at the stories of some of the high-flyers who blew their tech career by getting in trouble with the law.

Poacher turned Gamekeeper

'Please don't insult me by calling me a fraudster,' Tom X pleads. He likes to tell anyone who will listen that he was the man Fortune 500 and FTSE 100 companies once brought in to rescue their woeful security measures, after years of doing little to stop corporate thieving.

It was just his ill luck, he says, that a random internal audit for one firm he consulted for discovered that he had consistently helped himself to many of their confidential documents, sensitive information, and money.

He may be a thief and have a conviction for money laundering but he sees himself as a white-collared hacker and that matters to him greatly.

'I admit that I've stolen money and intellectual property but somehow felt that the way I did it set me apart from other criminals. It took years of skill to develop what I did.'

Though it cannot be said that he left his London-based technology consultancy business as he would have wished, with the cheers of thankful companies ringing in his ears, he undoubtedly managed to dodge rotten fruit being thrown in his direction when he refused to deal with media requests asking him to name the string of illustrious companies he had advised in return for money.

And that discretion has helped him since his release.

Just as all ex-cons have to find themselves a new role once their term of imprisonment is complete, so has Tom X.. He has returned to the IT industry as a security trouble-shooter after being offered several posts since leaving his cell.

'I had very good connections throughout IT, kept up with all the goings-on while in the nick, so I didn't have to cold call people when I got out. I'm thankful that some people see me in the round.

'The prison sentence ended a couple of relationships but I'm finding that following a different path after my release has helped a great deal. Redemption is very important to me,' he says, obliquely referring to his new-found status as lay preacher and God-fearing Christian.

A graduate of Oxford University and Harvard Business School, and son of an investment banker, he confesses that he did not foresee anything other than a swift rise in the industry during his early years as a software engineer.

After leaving Harvard with a brilliant reputation as a gifted problem solver, he worked on developing programs for a well-known software house then went into software design, then computer games.

At one point 'somewhere in the distant 1980s' he was turning over 'something well north of $350,000 each year.'

Now 51, Tom certainly doesn't look like a practitioner of hocus pocus, or even a flashy tech executive. His round glasses and neatly trimmed moustache give him the appearance of a dependable provincial bank manager from yesteryear. On close inspection, the pattern on his tie is made up of pictures of pink kittens.

He claims that he's back on his way to becoming one of the most sought-after IT security consultants in the US, even though he's officially blacklisted by almost everyone who knows his guilty past.

'IT directors and tech chiefs have the greatest respect for my skills and I openly tell clients where I've been for the last few years - banged up at Her Majesty's pleasure. It's my biggest regret in life but honesty does help to get deals'

'I'm back on my own two feet, don't owe anyone money and have been living an honest life for the best part of two decades. It feels great to earn a few thousand bucks a month.'

To prove he's a more honest man than in the past, he flashes me a cheque for $15,000, paid to him by one of the FTSE 100 companies who say they will have nothing to do with him.

He refuses to tell me exactly what he does for the company in question and indeed sees the defense of their reputation as a beneficent act.

'Most people in technology not only want their business to succeed and be profitable, but genuinely want to ensure that their customers secrets are safe with them and only them,' he says, without a trace of irony.

If a negative story about one of his clients breaks, Tom enjoys calling journalists and highlighting the elements that have made that business a success.

'I've always looked at talking to journalists from the point of view that I'm trying to make good things happen and communicate that good things are happening,' he adds.

'My story is not one of where crime has paid since I could have earned ten times what I do now had I not been stupid. I'm just fortunate enough to have seen my mistakes and stop running away from them.'

Among the Dead Issues

The lengthy shadow cast by David Y's trial for corruption looms large some seven years after his release.

At 6am on October 12 1992 the Jacksonville Sheriff's Office, and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives raided his house in the Northwest Quadrant of Florida's largest city.

They had been tipped off that the former multi-millionaire systems analyst, and the then vice president of a large telecoms and IT company, had an illicit stash of explosives in his back yard, a heroin factory in his loft and hard-core pornography on his computer.

He hadn't, but what the police found led to him being sentenced to five years in prison anyway. He was found guilty of multiple counts of fraud and of making false statements to regulators connected to one of the first online share scheme's that, in 1990, wiped millions of dollars from one of his company's accounts.

The judge at his trial amazed the court when he ordered the erstwhile golfing partner of a former US presidential aide to pay back $3.1 million to the company he used to run.

David Y 's false filings and fraudulent actions had inflated his company's sales by more than $9 million. He was accused of masterminding other online frauds in the UK, France, Germany, India and Canada, but lack of evidence in those not so tech savvy days meant he escaped heavier fines and a longer jail term.

After a series of financial disasters of his own, now broke and without a steady job, the man his peers once labeled as the 'ultimate professional' is 'at the bottom of the heap' re-training as a double-glazing salesman.

'I'm in need of some urgent PR,' he says, the comment partly due to the corrosive effect of being such a hated figure inside the technology industry.

'No one will touch me, even though I've paid for what I did and have been going straight ever since. Everything I did has been seen as very personalized. I've dealt with many technical directors or VPs of major companies and as far as they are concerned everything is down to the personality of the chairman or his assistant. And I've really balls-ed up that relationship. '

He loathes being outside the IT industry and continues to fight a battle to convince people he should be allowed back to run a company that once boasted of earning $1 million a month from its website alone.

'The company is still active and moderately successful. Though I'm not banned from becoming a VP or chairman, people think I'm too much of a liability. '

David puts all his present ills down to the people who run the industry, not his own stupidity.

'Look, the trouble with the technology industry is that the people at the top have created a very insular organization that breeds arrogance and cozy attitudes, and where the harsh realities of the business world outside are ignored.'

'I'm not pointing my finger at any particular company because all of them have this same view' he says. 'When I started up my business I looked at the world of IT through a positive prism, but from the outside I now see staff that fib and fudge when designing products trying to please an increasingly target-obsessed management. It's a culture that needs addressing.'

'But I still believe that I have something positive to give back to an industry that I love, and I should be allowed to do that. I've a suite of database management products I'm developing and am desperate to bring my expertise to market but no-one will back my ideas.'

'It says something about our society that people like to list what I lost in monetary terms: a $650,000 salary, so many millions wiped off the valuation of my company, and a billion-dollar turnover slashed overnight.

'I was so stunned by what I had done that it was impossible to see a way forward. Not only had I lost my job, but I had lost the only job I had ever wanted.

'I had never had any other ambition. Being the boss of a tech company had consumed my thoughts and my energies for so many years that I had never stopped to think about what I might do afterwards. It was a job I had thought I would have for life.

It's difficult to explain, but I felt that I had lost my future, that all the events and milestones I had mapped out for myself had faded. And without the structure and support network - drivers, personal assistants, financial advisors - and a full diary of meetings, my life seemed incredibly empty. Like many men of my generation, I had let myself be defined by my job, and without it I really didn't know who I was.

David Y's IT career may yet be resurrected. After having an out-of-hours chat with a headhunter, the law it seems may for once be on his side.

His criminal past may have had a negative influence on the recruitment process for a job for which he was turned down, and can now be challenged under discrimination laws.

'I know from my experience that recruiters discriminate all the time in areas not covered by law. They might discriminate against someone with ginger hair, for example, but there is no discrimination law - yet - that covers this but there certainly is for someone with a spent conviction.'

The Price of a Dodgy Past-time

Many companies are so terrified at the prospect of being accused of discrimination by possible future, former and existing employees that employment lawyers say that they work in a climate of fear, with employers desperate to protect themselves by every means possible.

Paranoia is now getting so bad that a yearly CV healthcheck is fast becoming the norm, and it was just this sort of internal inspection that ensnared Doug Z a $210,000 a year chief information technology officer with a leading investment bank.

The 38-year-old was tipped for promotion to the company's board, when he suddenly left the company this summer after an internal review of the university qualifications he had listed on his CV, when he joined the company fifteen years ago were found to be ropey - something which meant both shame and resignation.

His humiliation was probably worsened after his employers reported finding out that about his unsavoury part-time hobby of stealing female underwear from washing lines, from a social networking site, several blogs and a YouTube video. This sealed the case against him.

Although pleased with his work at the bank his immediate boss had no hesitation in sacking him.

'Nicking underwear was just a bit of fun. It was a prank and in any case I gave all the underwear back to the people I got it from' Doug Z , a former police cadet, maintains.

'I was brilliant at my job, earning a fantastic wage but no-one took this into account when they fired me,' he says adding that he is now suing his former employers for unfair dismissal.

Doug Z 's argument is that looking up his name on a social networking site was akin to going into his house and searching through his bedroom drawers.

'If there's an argument for me to exercise self-restraint then that rule should also apply to employers. After all, you wouldn't expect a potential employer to eavesdrop on a dinner party in your front room, would you? What I did was not illegal.'

The courts might yet take a different view. Doug Z 's case for lewd bahviour is slated for early December. If found guilty, his IT career could be another cut short by getting in trouble with the law.

The names and identifying details of the people mentioned in this article have been changed.