Colin Thatcher, a one-time Saskatchewan cabinet minister who spent 22 years behind bars for the murder of his former wife, is writing a book that he says will include proof his lawyer never received full disclosure of evidence during his 1984 trial.

Thatcher told Edmonton radio station CHED that he has letters proving the Crown denied him access to his file. He had harsh words for the provincial Justice Department.

"They will lie, they will mislead you, they'll actually cheat," he said, pointing to the wrongful conviction of David Milgaard, who spent 23 years in prison for murdering nursing assistant Gail Miller before DNA evidence exonerated him and convicted Larry Fisher of the crime.

A jury found Thatcher guilty of first-degree murder after JoAnn Wilson, 43, was bludgeoned and shot to death in the garage of her Regina home. He was granted full parole in November 2006.

Thatcher has so far completed 11 chapters of his book — tentatively titled Odyssey: Anatomy of a Frame. His plan is to continue writing this fall and winter, finishing early in the new year.

So far, he hasn't found a publisher. He admitted that reliving the early years of his experience in the justice system has been emotionally difficult.

"I'm trying not to be bitter, but there are times that I'm afraid some of it does show through," he said. "At the moment, I have to say I'm not having a whole lot of fun doing it."

Thatcher said he is resigned to the fact he will never be given the opportunity to overturn his conviction, but is confident his book will clear him in the court of public opinion.

In the rare interview, Thatcher also talked about his time in prison, calling it a "a horrible, horrible place."

He said he got through his sentence by minding his own business and never ratting on other inmates.

"I can honestly say that with all the different prisons I was at, never once did I have any concerns about going into that prison wondering if there was somebody that was waiting for me that had a score to settle or grudge against me," he told CHED.

Thatcher said he never asked to spend a single day in protective custody and even made lasting friendships, especially while serving time at Edmonton's maximum-security prison.

"There was a code at the Edmonton Max at that time … that until a guy does something wrong, nothing's going to happen to them. I'm very grateful to them for the help that they gave me to at least show me the ropes of the system so that I was able to survive."

Asked what he missed the most while in prison, Thatcher said it was his freedom.

"I envied people that were sitting at home and had the option of walking down to a convenience store if they wished," he said.

These days, Thatcher spends his leisure time attending football games — although he bemoans the performance of the Saskatchewan Roughriders — and lives at the ranch his family has owned for years.

At 68, he still breaks horses despite suffering the occasional bruised or broken rib. He credits his physical condition to the daily workouts he did in prison, as well as the restricted diet he went on when he had to have a medical procedure to deal with a genetic heart condition.

"Even at my age, I can do things now that I couldn't do when I was 20, from a physical point of view," he boasted.

"I should never have gone into politics, I should have stayed right on the ranch."

He can't imagine wanting to retire.

"No, I'll die working. I will probably die in a pen sorting cattle or something, and that'll suit me fine, to go that way."

Although he's had trouble adjusting to the technological advances of the last 22 years — he's embarrassed to admit that he still has difficulties with ATM cards — he has not had a problem with dealing with the public.

"In my home area where I am, I've had virtually no negativity," he said. "Now, I'm not saying that it's not there, but none of it has surfaced to my face, anyway."

However, he said he recognizes he no longer has the luxury of anonymity and so he is always prepared.

"Any time I go somewhere, I'm always ready to leave. I never go to a place where I don't drive myself because I want to have the keys to my vehicle so that if I have to leave, I can leave in a hurry."

And he said he is fully aware that he must never make a public misstep.

"I never forget I'm on parole."