Yes Magic Jack will accept calls from prisons but obviously this won't be free.
However, in order to use this, the prison must be using Global Tel Link. You can find out if the prison you want to call uses this by contacting them or going to www.globaltellink.com
Basically, all you need to do is
- Call the number of the prison
- Enter your Magic Jack number (including area code)
- Enter your credit/debit card details.
The person that you want to talk to in prison should be able to call you almost right away.
You can put money on the account for your prisoner friend to use, I think the options are $25 or $50 and in my opinion I would go for $25 first just to be absolutely sure it is working as it should.
So all you really need to check for now is that the prison you want to contact uses the correct system, if it does there should be no problem.
I hope that helps and that you are able to talk to your friend/family member very soon - good luck!