What do you call a country where the legal system is observed? I came up with a "nomocratic country", but that seems to be used extremely rarely. There is a Wikipedia page talking about the Rule of Law, but I cannot come up with a way how to twist it into an adjective (or adjective phrase, if there is such a thing) to describe a country.

The context

I found a sentence somewhere which reads "Since Czech republic is a modern legal country based on a democratical regime, there are fundamental human rights being guaranteed." and I am trying to figure out how to rewrite it. I got stuck with the "legal country". It is obviously wrong, but I cannot figure out what's better to say.

I think the expectation in most of the world would be for a lawful society.

Lawful

constituted, authorized, or established by law.

The opposite is lawless or anarchic.

A legalistic society is one committed to strict, literal adherence to the law or to a particular code, as of religion or morality.

But with Google N Gram Viewer, this (legalistic) is beat out by

• nomocracy (used 4.3 times more often today) and
• nation of laws (used 1.67 times more often today).

Since your update with context I would suggest the following:

The Czech Republic is a modern democratic country, and its laws guarantee fundamental human rights.

I think this reworks the sentence you suggested without resorting to uncommon terminology.