Readers who are interested in the question have probably noticed that I usually use "pled" in this blog. It sounds right to me.
The article by Messrs. Chandler and Boone is helpful:
Mr. Chandler's view (said to be minority) (footnotes omitted):
Use "pled." Boone needs to get out more—"pleaded" may seem fine on paper, but lawyers chuck the word when they head to court. A lawyer arguing a motion to dismiss doesn't say, "They haven't pleaded scienter." He says, "They haven't pled scienter."
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Twice, legal tabloid/blog Above the Law has asked its readers which they prefer—"pleaded" or "pled." Twice, strong majorities chose "pled." Check Westlaw or Lexis, and you'll find that judges use "pled" more often than "pleaded."
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Boone can wield a pen, but on this one, he's stuck in the past. Use "pled."Mr. Boone's view (said to be majority)
Use "pleaded." Chandler slips into hyperbole when he says that "everybody says 'pled.'" That, of course, isn't true. In fact, every legal and journalistic writing guide from the last 100 years has said that "pleaded" is the better choice.6 And for good reason: "Pleaded" better captures the past-tense-ness of the event.Their Concluding Remarks:
So there you have it. We'll leave it to you to decide who has the better of the argument.
But whatever you do, don't use "plead" as the past tense of "plead." That's just wrong.