If somebody is sentenced to life plus 5 years with the possibility of parole, how long do they actually have to serve? Or what does that actually mean?
If someone is sentenced to life in prison with possibility of parole, in Georgia, for sentences imposed from January 1, 1995 and June 30, 2006, the inmate is first eligible for parole after 14 years, and for life sentences imposed after June 30, 2006, the inmate is first eligible for parole after 30 years. In either case, if parole denied, the inmate is next eligible for a parole hearing after another 8 years.
The language "plus five years" is ambiguous as stated. I would not trust either a media report, or someone paraphrasing the sentence, to be accurately describing what the sentence was if they used this language. Instead, I would insist on looking at the actual language of the mittimus (which is what the court order summarizing the sentence imposed is called).
It could mean that there is a five year prison sentence being served concurrently with the life sentence, which would only be relevant if the conviction giving rise to the life sentence was vacated five years or less after the sentence started to be served.
But, it could instead mean that there is a five year prison sentence that is being served consecutively to the life sentence. Thus, someone would start serving their five year sentence when granted parole on the life sentence, subject to any earlier release on parole from the five year sentence, which would be available after one-third of the five year sentence is served.
Of course, a grant of parole is entirely discretionary. Someone serving a life sentence never has a right to be released from prison unless a parole board decides that it is appropriate to do so. And, even if parole was granted on the life sentence, the parole board would have no obligation to grant parole on a consecutively served five year sentence as well, when a parole hearing on that sentence became available.
In California, a life sentence typically means that, without being granted parole, commutation, or pardon, you will be in jail until you die. This differs from a capitol or death sentence, in that in the latter case, you are given a date where the state will kill you.
Additionally, in California, a lifer who has the option to parole, they may make their first petition to the parole board after serving 7 years in jail. Whether or not they get it is the board's determination and they take several factors into account (one of those being you are willing to admit guilt for the crime, your behavior in prison and several other factors such as victim statements, though this is not exhaustive.).
Other terms you might here are consecutive life sentences. Any consecutive sentence is served one at a time (so if you're convicted of three crimes and sentenced to 10 years for each, to be served consecutively, after 10 years, you have only served the time for one charge and need another 20 for the other two. If they are concurrent, then 10 years of jail will satisfy all 3 sentences.).
In this case, at most, the convict will serve 7 years for one life sentence assuming that they make their first parole, which is unheard of for someone serving a life offense (usually the serious nature of a crime that got them life will mean that 7 years is not enough). It's often stated that life is equal to 25 years, but this is more that 25 years is usually the maximum sentence with an exact value for a single offense... beyond that life is imposed. Again, at the point of life, barring a successful parole or a pardon/commutation, you are there until you die.