Sim, Mason perdeu mais de uma vez, de acordo com algumas fontes que encontrei.
De funtrivia , fórum, uma pessoa afirma que,
Mason actually lost two murder cases in the original series. But in one, "The Case of the Terrified Typist," he was misled by his client, and in the other, "The Case of the Deadly Verdict," his client was eventually cleared.
Outra pessoa afirma que,
Mason is known to have lost, in some form or manner, three cases-"The Case of the Terrified Typist", "The Case of the Witless Witness", and "The Case of the Deadly Verdict".
Mason also loses a civil case at the beginning of "The Case of the Dead Ringer", partly due to being framed for witness tampering.
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Na NPR, afirma que Mason perdeu apenas um caso. Entrevista com Barbara Hale, que interpretou Della Street no programa de TV de longa duração, fala sobre a perda de Perry Mason.
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perrymasontvshowbook.com afirma que Mason perdeu três casos.
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