Why does it matter?

Glad you asked.
There are so many things wrong, so many things that might never be fixed.
We know they are wrong.
A majority can agree they are wrong.
News reports confirming the well known wrongness are everywhere. Wrongness is deeply entrenched. Making it right is going to take a huge amount of effort.
It's that way for every cause.
It all comes down to People. Get enough people to move in the same direction and the "movement" will bring action to the "cause".

But some things can be fixed with the stroke of a pen.
It won't take anything more than that to fix this problem.
Sure, it would help to have as many voices as possible asking for action.
But the problem of John Richard Knock being jailed is fixable. It just takes a small action by one person with the authority to correct the excesses of our justice system.
In the United States, that person is the President.

So for me the answer is;
It matters because this is a wrong that can be made right. It wouldn't take an act of congress, or a committee, or a parole board, maybe it will, but it doesn't have to. All John needs is for the sole person with power to say OK.

But why should this matter to anyone else?
Maybe because it IS fixable, maybe because it's just the right thing.

It has mattered a lot to his family. Think about that.
If it were your Uncle or Brother or Son or Daughter. How would you feel if they were trapped in a prison system for something they didn't do?

It definitely matters to John's sister Beth. She has spent countless hours gathering information and organizing for sentencing reform, searching the World Wide Web for resources, and others in John's situation. Looking for someway to get recognition for this cause. Not just for her Brother but for all the other people caught in this perversion of justice. People who have been given excessive sentences just because some politicians want to claim they are "tough on crime".

Why should it matter to you?
You don't need to have the weight of the Department of "Justice" fall on you. People in prison got there by doing something wrong. For the few innocent people in jail it's just not worth the time and trouble to be bothered by it. Where do you even start? You've got enough to do just leading a regular life, holding down a job, making a living. That is how responsible people lead their lives.

But the average person isn't safe from this arbitrary assault on everyones civil rights. If you are caught traveling with cash money, and you are suspected of being in the drug business, your money may be seized along with your car or truck. It will be up to you to start the process of re-claiming it through suing in a civil action. Your property will be presumed guilty and if you want to get it back you will need to spend more time and money fighting for it in court. Perhaps you've got time and money to spend, regular people usually don't.

Most people are shocked and offended by this situation. They refuse to believe it could happen in this country. But it happens all the time. It happens to people who don't have the power to fight back. It happens to average people. People who can't afford to fight back, people who end up being labeled as drug dealers. Nobody is going to care what happens to you if you are a "drug dealer" you're going to get what's coming to you.

My Uncle John wasn't actually a "Drug Dealer" but he was convicted as a "King Pin". You can read a statement from him here:
http://www.johnknock.com/johnsstatement.html
You can also get more facts and background about his trial and the plight of others in similar situations here:
http://www.lifeforpot.com/

But wait there's more,
It should matter to you because you are lucky enough to not be targeted yet. If you are free, you are believing in an illusion that is one police action away from being shattered. The more you look for it, the more you will see drug raids destroying the wrong house. People being brutalized "accidentally". Family pets killed because they threatened police who were at the wrong address. This whole mindset is Un-American. Our inheritance is Government By the People and For the People.
We are now the People. Police are hired to serve society, they should not be given the power to steal from travelers on the highway or summarily execute family pets.
We have allowed a system of "Justice" to evolve which doesn't serve us. The system is built around expedience and convenience for Prosecutors.

Our "Justice" system has been incentivized with a profit motive. Law enforcement is looking for things to take, not to get criminals, just stuff, power and money. "Due Process" is for wimps.

You remain unconvinced, this issue doesn't matter and it's not your problem. Fine, that must mean it hasn't hit your family, yet. I'm fairly certain, given the trends and market forces involved, it's only a matter of time. Unless pressure is put on the people we hire to work in our interest they will simply work in their own interest.
Once you have "contraband" seized from you on a vacation or business trip. Or have your front door kicked in by a SWAT team who got the address mixed up. Or are labeled a "drug dealer" or "King Pin" because you used to know someone, once your seized property goes to auction and you realize there is nothing you can do about it. I think you will begin to understand that this issue matters but nobody is going to listen to you, not if you're a convict. Why should they?