Source: https://www.ridleylawoffices.com/blog/credit-card-defense-secret-weapon/
Timestamp: 2019-04-25 08:00:19+00:00

Document:
It’s terrifying to watch the process server walk away from your front door, and stare at the brand-new summons and complaint in your now-shaking hands. You don’t know what to do, the language is cryptic at best, and you’re pissed.
If the Plaintiff who put those papers into your possession was your credit card company, or other creditor, you need to file your answer, WITHOUT DELAY. You need to get an experienced debt attorney on the job right now. IF you don’t file, you will lose many of your rights, and if your creditor gets a default judgment against you, you lose a lot of leverage.
One of the least-known techniques for defending a credit card lawsuit is demanding a bill of particulars from the Plaintiff. A plaintiff who sues on an account is not required to set forth the specifics of your account in their complaint (Cal. Code of Civil Procedure § 454).
However, on written demand by the defendant, the plaintiff is required to furnish a copy of the account on which the complaint is based or be the Plaintiff is precluded from giving evidence thereof (Cal. Code of Civil Procedure § 454). This procedure, known as a bill of particulars, forces the plaintiff to itemize the total sum upon which the complaint is based, and which they are suing you for.
Demand for a bill of particulars is less often used than it perhaps should be. However, for the defendant in an action on a credit account, it can be a terrifically powerful tool.
Perhaps a reason for its declining use is that attorneys often fail to recognize that, in the appropriate action, a demand for a bill of particulars can be very useful in forcing the plaintiff to provide all of the documentation supporting their claim This is particularly true when the plaintiff is an assignee of a finance or credit card company and may not have all of the documentation.
The demand for a bill of particulars must be in writing, and the bill of particulars must be delivered to the requesting party within 10 days, 15 days if the demand for a bill of particulars is served by mail. And if the original complaint or cross-complaint was verified the bill of particulars must also be verified.
If, after furnishing the itemization, plaintiff finds that it was incomplete or incorrect, plaintiff must seek leave of court (by noticed motion) to amend the bill of particulars just as he or she would to amend a pleading.
The bill of particulars furnished by the plaintiff is treated as an “amplification” of the pleadings. As such, it has the effect of a pleading. Consequently, at trial, plaintiff is limited to the items and amounts specified in his or her bill of particulars. No additional items can be shown. See Baroni v. Musick (1934) 3 Cal. App. 2d 419, 421.
(5) quantum meruit-Caruso v. Snap-Tite, Inc., (1969) 275 Cal. App. 2d 211, 214-215.
Even though the code authorizes a demand for a bill of particulars in an action “on an account,” it is not available in an action on an account stated. Distefano v. Hall, (1963) 218 Cal. App. 2d 657, 677.
An account stated is a new agreement by the parties which supersedes the original contract and account. Jones v. Wilton, (1938) 10 Cal. 2d 493, 498 .
Any action on it is therefore based on only the final balance agreed on by the parties and not on the original individual items of account. Hallford v. Baird, (1938) 27 Cal. App. 2d 384, 398. Therefore, itemization of the account is not possible.
If the information furnished is deemed too general or incomplete, the defendant may make a noticed motion for a further bill of particulars. Burton v. Santa Barbara Nat’l Bank (1966) 247 Cal.App. 2d 427, 433.
If plaintiff does not deliver the bill of particulars, the Defendant may move the Court to bar the plaintiff from introducing evidence at trial in support of the account claimed.

References: § 454
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