In 2005, Michael Brown hit the headlines when he gave more than £2m to the Liberal Democrats.
But his stay in the headlines was swiftly followed by 12 months in prison for perjury.
This week, on the Politics Show, he speaks about what he has learned from his experience on the inside, and what he now wants to tell politicians.
This is a transcript of his interview with Gillian Hargreaves.
Gillian Hargreaves speaks to Michael Brown
Gillian Hargreaves: how many prisons did you go to?
Michael Brown: I was in a total of seven prisons, starting at Wormwood Scrubs, moving down to Stamford, then moving down to Elmleigh in Kent, then getting moved up to Peterborough, while I was being told that I was going to Pentonville but discovering I wasn't when I ended up in Peterborough, then getting moved back to Wormwood Scrubs and finishing up in Wandsworth. Nearly twelve months, so seven prisons in twelve months.
GH: People call it churn in the prison service. What kind of impact does that have on the prison service?
MB: It's one of the worst things that can happen to an inmate, to be constantly moved, because you get into a prison and you think that you're going to be there for the duration of your sentence, so you make the best of a bad situation, you make the cell your own, you get to know your inmates and you get to know everything else, and then all of a sudden you get moved, and there's no notification of the move - the most you ever get told is at eight o'clock the night before, or slipped through the door at midnight that you'll be moved the next morning.
And that's the worst thing, because you can't tell your family. So you end up going, like I did, a hundred and fifty miles up north, and your family has no idea where you are, and I think that's wrong. when an inmate's sentenced, he should be at the prison he's meant to be at for the rest of his sentence, and if he's at an open prison he should be at the open prison as soon as he can, or if he needs to be at a high security prison he needs to be at a high security prison.
But moving people around the country is not only a huge waste of taxpayer's money, moving a prisoner costs hundreds, if not thousands of pounds, but you wake up and have to start your life all over again. And that's the worst part, you have to start your life all over again from the beginning.
GH: Isn't prison a soft option, looking at the papers - three meals a day, TV?
MB: A soft option! Well in that case I would recommend that anybody goes and does it and see how soft they think it is. It's not a soft option - it's prison, it's incarceration, you are separated from your family, you have a loss of liberty. You are locked up - in some of the prisons I was in - for up to 22 and a half hours a day, and you are let out for half an hour and told either call your family or have a shower - choose. You know, it's not a soft option, and it can't be seen as a soft option.
GH: You did witness some pretty grim things while you were in prison. Could you give us a flavour of some of the experiences you had?
MB: I must say, to start with, I was fortunate while in prison. I was never a victim of bullying, I was never a victim of harassment by any officer, I was treated well, but that was because I treated everybody else well. You have lost souls in prison, which is what I call them, which is the people that decide that they want to take their own life. You know there's a very fine line between sanity and insanity. You know I had people in front of me try to kill themselves.
One guy tried to take the stitches out of his arm and kill himself: he was ripping the stitches out of his arm and smearing blood all over himself. You know at that point that person's not sane. That can be stopped if it's seen and nipped in the blood, and I think all suicides in prison can be stopped if there's enough time spent with the individual inmate.
Another inmate tried to hang himself in front of me, another inmate tried to slit his wrists in front of me. You know, this is not normal - these people should not be in a prison, they should be in a secure mental unit, and that's where they need to be.
GH: There will be people watching this who say if somebody's committed a violent crime, or a drug crime, then actually I don't really care if his life is made uncomfortable. Why is it important that we have a prison service which is working better than it is at the moment?
MB: The simple answer is that we're all human beings. Most people in this country know somebody or know of somebody who has been to prison. So I would say to people think of it as though it was your brother or sister and ask if you want them treated that way.
And the answer would have to be 'no', and just because he's not your brother and she's not your sister doesn't mean you owe them any less. You know it's basic human rights. Putting three people in a cell ten by twelve is inhumane, locking somebody up for 22 and a half hours of the day is inhumane, and that's where I think the system has gone wrong.
GH: And also in financial terms and as a public service, what are your thoughts about that?
MB: Well I think that there is a problem in the prison service, where the government run prisons are really not accountable, and they are holding places. And I think that's wrong: I think when a judge sends a man down, he sends him down because he says he is not fit to be in society.
The prison's job is then at that point to take him out of society and train him to be a better member of society. You cannot take somebody who has been in prison for fifteen years, or twenty years, or five years, and once he's done his sentence, just open the door and throw him out onto the street, because he will commit another crime, because he is a recidivist.
There's no accountability. On the private sector there is accountability, and that's where I think the private sector works a thousand times better than the public sector.
GH: And you had some direct experience of that, didn't you?
MB: I was in Peterborough, which is a privately-run prison, and the difference is 1000%, where the minute you walk off the van you are treated with respect by an officer, and it's if I am polite to you, you're going to be polite to me, and that defuses any situation.
The way they work on trying to help an inmate due to be released is a thousand times better than it is in any private prison. You know they sit there trying to go through the housing problems, the unemployment problems, and that's how they try to help them, where I didn't see that in any of the public prisons.
GH: For the taxpayer the cost of sending people to prison has risen to 1.92 billion each year. It's costing about as much to run the secret service as it is to run the prison service. Are we getting value for money?
MB: No, absolutely not. The sentencing of prisoners is incorrect, the categorisation is incorrect - by categorisation I mean what level of security of prison they have to go to. The remand of prisoners: now remember that remand prisoners are all innocent until they have been proved guilty by a jury of their peers.
You can't remand all these prisoners. If you released the remand prisoners now that are non-violent - I'm not saying you have to release every prisoner that's on remand - but ones that are not going to be a danger to society - you know tag them, put them on curfews, then you'll create 8,200 places inside prison. You know there's where the financial problems ease. At the cost of £40,000 a year to keep a prisoner, who's technically innocent, that's wrong.
GH: You served a year in prison. What's the effect been on you? Has it changed you?
MB: It has: I can honestly say it grounded me. The first couple of months in prison worked for me. My ego deflated by about 1000%, you arrogance deflated by 1000%. The first couple of months grounded me, and I came into touch with people that I probably would not have met in any other walk of life were I on the outside, and some of these people will be my friends for life because they see you at your worst and they take care of you. The other 11 months are another story, but the first couple of months actually worked. It wasn't as scary as I thought it was going to be.
GH: There have been other people from the political world who have gone to prison for one reason or another and who have come out and said I want to start talking to politicians and so on. What are your hopes for yourself?
MB: We're called the gang of perjurers: scourge of society. I didn't write any books in prison, I haven't done anything like that at all. I have come out because I am a fairly high profile person, so I can use my voice properly, and that's what I want to do. I don't think going to trusts and having them inspect prisons works.
You need to go to people who have been inside prison and have lived in the prison system to say what's wrong, as opposed to standing there and saying 'this is what I think is wrong'. You know, I've been in 'B' category prisons, the second-highest category in the country, to being in an open prison: I've seen all the different levels. I'm happy to talk to any minister, shadow or government minister, as long as they want to take my suggestions real and not use it just to write a nice paper about it and stick it in the filing cabinet.
GH: Do you think it is high up the political agenda? Politicians have said to me during the course of this programme that there aren't any votes in prisons.
MB: I think that's ridiculous. I think that's absolutely scurrilous. These people are human beings and you have to treat them as that. We have a right - it's not even a right - it's a necessity to treat these people as human beings. And there's no vote in prisons, then let's just lock them in and throw away the key - that's wrong, that's inhumane.
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