If he does have to go through some sort of parole, what's involved with that? Weekly meetings? Can he do this in his home state rather than the state in which he was convicted and served his time? How do they transfer that sort of thing? Is it likely that he might just drop off the radar? Big case load?
As RJK said, commuting his sentence doesn't make it go away. Most times, a person getting out of prison for 'good time' doesn't mean they've served all their time, only that they're being released early and go on parole.
He'll have to meet with his parole officer, fill out a bunch more paperwork, let his parole officer know where he lives/works, hangs out. He'll be told the conditions of his parole (usually no drinking, no convictions of new crimes, no hanging out in certain places such as casinos/bars, may even have restrictions on who he can associate with). He'll find out how often he'll have to check in and how much his parole supervision fees are going to be - and how he's to pay those along with the restitution/fines he may have from his conviction.
It is possible to have a parole transferred from one state to the other. It involves a lot of red tape and miracle granting, for the most part. Usually the state he wants to go to will have to agree to take on the supervision duties, the court that convicted him will have to agree to let the parole be transferred, and the state in which he was convicted will also have to agree to let him go to the other state. Usually, as I stated, this takes a minor miracle to allow it to happen.
Leaving the state, or even the area in which he is supposed to be, will require a travel permit. Most states have regulations regarding registration for felons coming into their area. In Nevada, it means you spend any time more than 48 hours in an area, you'll need to register with the local sheriffs department. A condition of the travel permit may be that they check in with the sheriffs department as soon as they arrive.
Drop off the radar? Only if he purposefully absconds. Which can be as simple as missing a meeting with his parole officer. Depending on the officer and the suspect. Basically, it's up to the parolee to make sure to follow the terms of his parole otherwise it's back to the big house for them. And depending on how they fail to follow their parole, it could involve new charges that will send them to prison for even longer.
AND, any contact with law enforcement should bring up the fact that they are on parole. A PPCN will most likely be done with the officer giving certain information to be sent to the state parole/probation office. If there are violations of the parole (such as a felony DUI guy being drunk) then they may decide to do a parole violation and have him taken into custody. Then his parole officer will have to come down and decide whether or not to release him from custody or ask for a violation hearing to be held. This PPCN is RARELY sent to the guy's actual probation officer - normally it's someone in the state office who looks at the conditions, what is going on at that time and then decides to hold or not hold. So it's possible a hold will be placed that the guy's actual parole officer may not have wanted.
What RJK fails to mention in discussing the 'records check' is that a CJIS (state) check usually automatically does an NCIC (federal) check as well. And there are times when a traffic stop WILL ask for a more indepth records check as well. Such as when the person is in a vehicle with a weapon. I've done it quite a few times under this situation. Also, if the person is on active parole/probation then that fact should come up as well with just a regular records check. As well as any possible cautions on the guy (such as a conviction for a violent felony or some other reason for the officer to be cautious of the person with whom they have contact).
Okay, this is probably a lot more information than you wanted but hopefully it helps. Be sure to ask followup questions for anything you may need for clarification or to create a more realistic situation for your character.
Rabe...