Nor sure what the situation is in the US but generally probation and parole are different things altogether.

Parole is a provision that the offender is allowed to complete the term of a sentence of imprisonment without being confined in recognition of their promise not to reoffend and subject to a return to prison at the discretion of the judiciary.

Probation is a sentence whereby the offender is placed under the authority of the court (the court has probate) for a set period of time. Probation usually replaces imprisonment although there may be imprisonment if the terms of probation are not met.

Since a person on parole is technically serving a period of imprisonment, and an offender is debarred from voting when imprisoned, it follows that the right to vote is removed during parole. I see no evidence at all that probation involves loss of voting rights. I certainly see no evidence to support your assertion that in California: 'Once you are released from prison, you are considered a "Felon" for life, and never allowed to vote again = for your entire life'

I will go back and look at this some more, because you point out some important distinctions.

Keep in mind that it isn't unusual for CA prisons to release prisoners early and put them on both parole and probation, so they still cannot vote.

If the terms of probation are not met (which can be very simple violations, like having a beer) then you are once again blocked.

Interestingly, voting is not a constitutional "right" AFAIK, but there are fundamental rights that are taken away permanently.  Personally, I don't think that someone who has committed a felony should be blocked from receiving a scholarship to attend college for instance, nor have their "fundamental rights" taken away permanently.

But what purpose is served by taking away the right to vote?  If a lot of people are doing something that is considered "criminal", then perhaps the laws need to be changed. 

Drinking beer when you are 20 years old is a serious crime, but should it be?  I once asked a friend in Italy what the drinking age was there, and after thinking about it, she didn't think there was one.  She distinctly remembered going to the local grocery store as a small child and bringing home wine and bread - all by herself.

If a lot of people are turned into criminals by ridiculous laws, then they will not be able to vote in a way that changes these laws.

- Companies will not hire you because their business insurance bars them from hiring people with a criminal record.

- If you try to start your own business so that you can have a job, it is nearly impossible to get a contractor license and business licenses are harder to obtain.

- If you do manage to get a contractor license, it is hard to get the required insurance.

- No public funding to further your education

- Housing is much more difficult to obtain

- You are barred from ever owning a gun (I know you don't care, but that is an important right in the US)

- If you move into an area, people will look up your name on the internet, see that you have a criminal record, and won't let their children play with your children.

- It is just a hair trigger of a parole or probation violation to get put back in jail, so essentially you have no voting rights.

I know people who have gone through this and it is a big challenge.

IMHO, this is essentially being treated as a felon for life.