Why is »is« used here instead of »has«?

Question

I've been watching a TV show that its story line goes back to the sixties, and I encountered a weird sentence being spoken in the TV show.

• The court magistrate is determined that you will live out your remaining days in here.

The problem with aforementioned sentence is that it lacks the required 3rd person auxiliary verb, Has, and instead it is filled with a non-sense 3rd singular verb, is. Is it a legit sentence? If so why is it used like so?

UPDATE:

Both of the answers are great and if the system allowed me, I would pick both of them as the best answer. I have chosen the first answer because it was published earlier than the second one and it includes more information. I appreciate both of you, well done!

Answer 1

Without context, it's difficult to say; but the sentence may be parsed as grammatically acceptable in two different ways:

1. The past participle determined here may be employed not as a verb meaning made the determination, decided but as an adjective meaning "unwavering, insistent, adamant* —"The magistrate wants you to live out your days here and cannot be persuaded otherwise."

2. You may have heard The magistrate's determined and interpreted the 's as is when in fact it represented has.

In any case, this is an unusual sentence. Even given a mildly literary tone and a 50-year-old setting I can't imagine a contemporary US writer employing the expression "court magistrate". Modern US English doesn't use magistrate for any sort of officer outside a court of law, and the title usually designates the officer who presides over a minor court, not a court competent to impose life sentences.

Answer 2

Yes, the sentence is sensical and logical. When the auxiliary verb "to be" is conjugated and followed by what looks like a past participle, in this case "determined," it is not forming the present perfect tense (which seems like what you are expecting). This sentence actually just uses "to be" normally. It is describing the magistrate as determined, which means "having made a firm decision and being resolved not to change it."

Answer 3

"Is determined" and "has determined" give it two similar but different meanings, both of which could possibly be valid.

As others have answered, it's hard to determine out of context, and it could possibly be a misreading for has.

But "[He/she] is determined that ..." would mean he is in a state of being determined; "determined" meaning "having made a firm decision and being resolved not to change it." It's saying "He/she = determined ...", determined being an adjectival (or participle), form of the verb.

"[He/she] has determined that ..." is using the past tense of the verb "to determine", as in to decide, or ascertain. So basically, "[he/she] decided".

• Note: for simplicity I am abbreviating "the court magistrate" as "he", but take it to mean either pronoun, "he" or "she".