GMAT Sentence Correction (SC) | Defense Attorneys

That is very subtle observation Qwerty

To me, a comma should be inserted after 'but' -
Defense attorneys have occasionally argued that their clients' misconduct stemmed from a reaction to something ingested,but , if criminal or delinquent behavior is attributed to an allergy to some food, the perpetrators are in effect told that they are not responsible for their actions.

the sentence reordering clarifies it -

Defense attorneys
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