In my opinion, zero. Facts are facts, and it's not exactly new that prisons in the US tend to be shitholes.
In any case, my curiosity had nothing to do with her credibility. I was curious about how she drew herself versus how she drew others. Why she was in jail speaks to some extent as to who she is, and fills in a little more of the mental picture of her.
We accept this error when we have to do some fast thinking and the consequences of being wrong are small, but the moment you make this flawed logic the general rule is the moment you lose any chance at establishing the facts.
And credibility is a measure of how close their assertions are to the truth, how is that a logical error?
Or, rather, the area of philosophy where only the class of facts which can be certainly described as such are the facts of having particular present sensations (whether the kind that present as sense-data or the kind that present as memories) is a fact, and all other ideas about the world are either axioms or conclusions supported on the basis of either axioms, sensations, or a combination of the two.
Of course, when you leave that area of philosophy, you are in the area of fuzzy and imprecise thinking, so its not a bad area of philosophy to be in.
Human rights are called human rights because they're universal and apply to every human being, no matter the circumstances.
And I personally don't care about how exactly one landed in prison - for minor offences or major, that inmates do not have the right to shower daily is just fucked up. Or that sexual violence or drug dealing in prison seems to be widespread.