A number of investors in Dublin have lost substantial sums of money through insurance schemes arranged by former broker Mr Michael O'Riordan of Castleknock.

Mr O'Riordan has been the subject of a number of Garda investigations into "churning" and other allegations of mis-selling of insurance, but no charges have been brought.

The Irish Times has seen documentation relating to insurance deals which Mr O'Riordan sold to a number of people.

Many had little knowledge about the workings of insurance and lost considerable sums of money - in some cases the vast bulk of their savings - after their dealings with Mr O'Riordan.

Mr O'Riordan, a former director of brokerage Park Life and Pensions, is the subject of at least five complaints to the Garda of which The Irish Times is aware. When contacted at his home, he said he had "no comment at all to make".

In the early 1990s, Mr O'Riordan placed hundreds of thousands of pounds worth of business with Friends First, Guardian Assurance, Norwich Union and Canada Life, as well as Irish Life. Other insurance companies may also have been involved. Friends First, among others, has refunded premiums in some cases.

One couple entrusted Mr O'Riordan with their £20,000 in life savings. The broker persuaded the couple to put a £22,000 lump sum into an Irish Life life assurance single premium bond. But within a year he encouraged them to break the money up and place it with a variety of insurers including Irish Life, Friends Provident and Norwich Union, in smaller lump sums.

However, he redirected the funds into annual bonds where the companies expected similar lump sum premiums every year. Because of the high commission associated with setting up each policy most of these lump sums were depleted from £5,000 investments to sums well under £1,000 within a year.

Overall, between October 1990 and December 1992, the broker had persuaded the couple to part with £30,255. The surrender value of the policies in 1993 was just £2,237 but with a refund of £5,700 and other credits the family's total loss was more than £20,500.

So far, Friends First, formerly Friends Provident, has ruled out paying any compensation to the couple. Irish Life is still considering doing so.

Another young couple went looking for a mortgage to buy their first home before getting married. Mr O'Riordan persuaded them to part with £400 to simply apply for the mortgage and then told them the first year's life cover had to be paid for up-front.

As this was an endowment mortgage it imposed a heavy up-front burden on the couple. But worried that the bank might take away the offer as they were self-employed, they did what was instructed. Mr O'Riordan had bought a heavily loaded policy from Canada Life and had got a large commission payment on the first year's premiums.

This couple were fortunate and the life office agreed to reimburse them and refund their premiums.

Another man was also approached as he was buying a property. He only wanted a mortgage policy but ended with a new pension policy without having applied for it.

According to this man, Mr O'Riordan asked him to sign a number of forms to ensure he got the best possible mortgage deal. But months later he noticed that his direct debit for a pension had another life office's name on it.

Both pensions were for the same amount of money and he only realised when he saw the payment was being taken by Friends Provident rather than Irish Life on his statement. He said that his statements only arrived every three months and it was the second statement before he noticed the change in destination for the money.

Mr O'Riordan had cancelled his policy and taken out a new one with another group, again winning significant extra commission. It was almost a year before this was sorted out but the man was refunded all his premiums by Friends First. Irish Life also offered to reinstate the man to his original position, subject to outstanding premiums being paid, but he declined to accept the offer.

Others have sought recompense through the courts. A widow brought Mr O'Riordan and Friends Provident to court. The case was settled for £3,000 but this was reduced to almost nothing after paying legal fees. And she had lost £7,000 of her money. The money had been invested in an annual premium product rather than a single premium and the woman only realised when the next year's premium was demanded by the life office.