How far to go back to approach an argumentative flaw?

[LSATmaniac2.0]

A quick question about a specific LSAT question, which translates to a more general idea: PT#35, S4 (LR2) Q. 7. The question revolves around an attorney asking you to find a man guilty. Why? Even though there were no eyewitnesses, the defendant has a violent character. Why does he have a violent character? Because someone else testified he shouted and threatened her. Why should we believe her? Because the defendant didn't refute her testimony.

So should we go all the way to the end of the logical chain of reasoning here? Approach from the 'didn't refute' because its the strongest flaw/without this piece of the argument everything before it falls apart? Or work from the conclusion backwards, looking at the violent character, then the example of violent character, then the non-refutation? Also, would it be okay to bring in outside assumptions about law, to say that character attacks, though not legitimate on the LSAT, are something [allowed] to be considered in a criminal case?

Any suggestions as to approach or weight to be assigned to the specific positions of flaws would be much appreciated. Thank you!

LSATManiac2.0

[Claire Horan]

In answer to your question "how far to go back," I would just say that you should prephrase all of the flaws you see in the entire argument, from beginning to end. There are multiple flaws in the reasoning in this argument, as you recognize, but only one of them is listed. Another flaw would be that even having a violent character does not prove that someone assaulted someone else in a given instance. Another flaw is that violent speech does not necessarily show that someone has committed or would commit physical acts of violence...You get the picture. You should try to be aware of as many flaws as possible, since only one will be listed as an answer choice. The other answer choices are either not flaws, not stated in the argument, or opposite of what the argument says.