What is the difference between a principal in the first and second degree and a accessory in the second degree?

The common law recognized distinctions between the actual perpetrator of an offense (principal in the first degree), and accessories before the fact, at the fact (principals in the second degree), and after the fact. (People v. Woods (1992) 8 Cal.App.4th 1570, 1581-1582, 11 Cal.Rptr.2d 231.) California law long ago abrogated the distinction between accessories before the fact and principals in the first and second degree. ( 31, 971.) While our law still recognizes a distinction between principals and accessories after the fact ( 32), since the enactment of our original Penal Code in 1872, section 31 has provided, in relevant part: "All persons concerned in the commission of a crime, whether it be felony or misdemeanor, and whether they directly commit the act constituting the offense, or aid and abet in its commission, or not being present, have advised and encouraged its commission, ... are principals in any crime so committed." ³

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