Controlling authority comes from many sources including common law, statutes, regulations promulgated under those statutes and the Constitution itself, both federal and state. So, commenting on a quote like this is difficult out of its context. The common law has developed through the centuries and up to the present by way of decisions written by the courts. But, the other sources are always present and all attorneys need to know all of them for the Bar Exam.
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Law Offices of Andrew D. Myers, North Andover, MA & Derry, NH provide answers for informational purposes only. Actual legal advice can only be given by an attorney licensed in your jurisdiction, thoroughly familiar with the area of the law in which your concern lies. This creates no attorney-client relationship.
If you are in New York, it could mean that "Justin" only went to law school for a year and then studied in a lawyers office prior to taking the bar exam. New York is one a handful of states that still permits this practice. It could also mean that Justin is trained like every other American lawyer (except those in Louisiana).
If you found this answer helpful, let me know by clicking the "Mark as Helpful" button at the bottom of this answer. This answer is provided for informational purposes only. This answer does not constitute legal advice and it does not create an attorney/client relationship. More importantly, the information contained in this answer should not be relied on. You should consult an attorney who practices in the relevant area of the relevant jurisdiction.