The counter-accusation is a defense strategy by which the accused

— Acknowledges the existence of the facts (the moped was burned) and their qualification (it is a misdemeanor).
— Denies being the author of the misdemeanor, and attributes it to someone else, S. Stasis.

Accuser: — You stole the moped!

Among other possibilities, the accused can countercharge:

— a third person:
            But it’s not me, it’s the boss!

— her accuser:

— of the misdemeanor of which she is herself accused:
           You stole the moped! it is the one who says who is!

— of another misdemeanor:
            And you stole a backpack in the train!

The reply (3) can be taken as an implicit admission and can also be used to allow the prosecution of the new accused.

Examples of counter-accusation

The counter-accusation strategy works as well in the informal setting of the family as in some types of courts.

It is reported that the accused in witchcraft trials in the Basque Country in the 17th century used this procedure.

Shortly before the sending of the royal commission of which de Lancre would be a part, significant events had already taken place, in the same places, and with the same characters that we will see reappear in the text of the Table: Local rivalries between family groups had given rise to accusations of witchcraft, an expeditious but disastrous way of getting rid of the rival group, which in response makes use of the same procedure.

Pierre De Lancre, [A Picture of the inconstancy of evil angels and demons, where it is amply spoken about sorcerers and witchcraft,] 1612 [1]

The strategy  works dramatically in political trials, especially if the accuser is the judge.

The láogăi “is a re-education through labor camp in the People’s Republic of China” (Wikipedia, Laogai).

Finally, as we have seen in the laogai, whoever accuses, in communist China, is always right, since he is armed with untouchable quotes and slogans; you almost systematically worsen your case by defending yourself. The only effective response is therefore a counter-accusation at a higher level: whether it is well-founded or not is of little importance, the main thing being that it is expressed in politically correct terms. The logic of the debate thus leads to a constant widening of the field of attacks, of the number of attacks and of the number of those attacked.
Stéphane Courtois & al. [The Black Book of Communism] 1997 [2]

It has a lot of weight in the people’s court and the media tribunal.

You are fake news!”.
Trump’s Impeachment Defense Borrows an Old Karl Rove Strategy — Ed Kilgore (The Guardian, 11. 13, 2019)

There’s one Rovian strategic principle that Team Trump is following to absolute perfection before and during the impeachment proceedings the president now faces, as explained in a 2005 academic discussion of Rove’s campaign modus operandi :
            Tactic #3: Accuse Your Opponent of What He/She is Going to Accuse You Of
This is another preemptive tactic, in which Bush has launched his campaigns by accusing his opponent of his own weaknesses.[3]

[1] Pierre De Lancre. Tableau de l’inconstance des mauvais anges et démons, où il est amplement traité des sorciers et de la sorcellerie, 1612. Introd. and notes by Nicole Jacques-Chaquin. Paris, Aubier, 1982, p. 8.
[2] Courtois Stéphane, Werth Nicolas, Jean-Louis Panné, Paczkowski Andrzej, Margolin Jean-Louis 1997. Le livre noir du communisme – Crimes, terreur, répression. Paris, Robert Laffont, p. 582