Legal experts and police officers expressed shock at the findings, which were made in a study of the results of the tribunal's latest 200 hearings.
The study, details of which will be broadcast in a Dispatches documentary on Channel 4 tomorrow, also found that 78 solicitors, found to have misused their clients' money, were not struck off.
Michael Zander QC, a professor of law at the London School of Economics, said: "I'd rather assumed, as I think most solicitors assume, that any improper handling of client monies will automatically lead to you being struck off."
Of the solicitors in the survey, 54 were making at least their second appearance before the tribunal and 39 had been fined at their previous appearance. The study revealed that 21 of the 39 were fined again but were still not struck off.
The survey will increase pressure for reform of the way the legal profession is regulated.
Even Barrie Marsh, the president of the tribunal, was surprised by the findings. "I'm amazed by that," he said of one of the cases. "Criminal offences involving dishonesty - I would be amazed if the solicitor was not struck off."
Among the cases featured in the survey was that of a Croydon solicitor, Terry Mitchell, who was allowed to continue practising by the tribunal, despite having served a jail sentence for a building society fraud. He was eventually struck off after an appeal.
Other solicitors who have recently been allowed to continue working include Patrick Macavoy, from Slough, Berkshire, who was fined pounds 1,500 for possession of child pornography earlier this year. Indira Maharaj, a north London solicitor, was convicted of an attempted mortgage fraud last year, but was allowed by the tribunal to keep practising after it was said the conviction had almost driven her to suicide.
The workload of the Office for the Supervision of Solicitors, which receives complaints about solicitors and decides whether they should be referred on to the tribunal, has doubled in the past two years to about 40,000 complaints a year. Less than 1 per cent of complaints are passed to the tribunal and receive a public hearing.
Martin Mears, a former president of the Law Society, said: "I think of the reputation of solicitors and it's bad for our reputation that our shop window body, the OSS, deals with complaints in the way that it does."
Dispatches also reveals details of a Law Society study on the OSS. It found that half the 300 complainants gave the OSS a rating of between zero and three out of ten for the way their complaint was handled.Reuse content