Is release for good behaviour up to the original sentencing judge?

I have been hearing a lot of anger lately against Judge Persky because Brock Turner was released three months early. Persky did the wrong thing by only sentencing Turner to six months. But was the early release actually his decision? Or is that up to the jail he served time in?

Depends on local and state laws. In some states, it can be very much up to the judge only. In other ones, the local jail/sheriff/prison warden/parole board have broad leeway. And everything in between.

No idea what the relevant applicable California statutes are.

I’ve watched enough movies by now to know that parole is up to the parole board which is comprised of one black lady, one old man in a bow tie and a young, charismatic, curly haired dude who asks if you’re truly repentant for what you’ve done.

California has a big jail and prison overcrowding situation and there have been lots of lawsuits: the result is a great many convicts being released early.

For example remember Lindsay Lohan? “A judge determined that Lohan had violated the terms of her probation by missing several mandatory classes and meetings. She was sentenced to 90 days in jail, followed by 90 days of inpatient rehab treatment. However, Lohan served only 14 days of the jail sentence, due to overcrowding.”
https://en.wikipedia.org/wiki/Lindsay_Lohan

In the USA, there are 50 separate states, each with different laws, and within each there are many counties & cities with local jails, so there is a whole lot of possible variations in this.

But in general, the authority/involvement of the sentencing Judge ends when the sentence is given. It usually goes something like “sentenced to the custody of the Minnesota Department of Corrections for a term of 300 months (25 years) and to pay costs of …”.

After that, it’s up to the Department of Corrections to decide what prison to send him to, what work he will do in prison, and when he will be released. Normally, there is a Parole Board involved in deciding on release. Often, there are normal procedures relating to release. For example, here in Minnesota, prisoners who do not cause problems in prison are eligible for parole after serving 2/3rds of their sentence.

The Legislature is involved, by assigning minimum & maximum sentences for crimes, and by setting up a Sentencing Guidelines Commission, which created a table of standard sentences for various crimes, taking int account aggravating factors & the offenders past. Judges can choose to depart from these norms, but they must document their reasons in the legal record. But the Legislative influence is all beforehand; they can’t change the sentence once it has been given. The Governor can reduce it, via pardons or commutations.

So the main control the presiding Judge has over release is in how long he sets the originasl sentence; after that the judge has almost nothing to do with it.

Not in states with TIS (Truth in Sentencing) laws. Like Wisconsin. There, since 2000 the sentencing judge decides how long the felon will remain in prison, and how long he’ll be on probation afterwards. Corrections authorities have no say in the matter. Good behavior does not get him out sooner, and bad behavior doesn’t keep him in longer (unless he gets convicted of another crime while in prison.)

This change in law has resulted in folks staying in WI prisons longer than they used to.