The precise legal definition of a cause of action is important to understand for legal professionals today.

For many legal practitioners within the State of California, a “cause of action” (or “CoA” as we’ll sometimes refer to it here) is synonymous with litigation – and for good reason. At its core, a CoA is what makes up a valid lawsuit; preparation, as always, is key.

Ultimately, a CoA is the state law equivalent of the “claim for relief” set forth in Federal Rule of Civil Procedure, Rule 8. It is the legal theory and corresponding set of facts that gives one litigant the right to seek judicial relief against another. 

And while it’s certainly possible to get highly academic and historical about this common mechanism, we’re not going to do that here.

In this article, we simply aim to explore what you need to know about causes of action within the California judicial system – from properly pleading a CoA to the mistakes that might lead to the dismissal of one or more CoAs within a complaint. 

And, just for good measure, I’ll finish off by sharing the best tip I ever received for drafting bulletproof CoAs in California.

Legal definition of a cause of action

The legal definition of a cause of action refers to a set of facts or circumstances that give an individual the right to seek judicial relief. It represents the legal grounds on which a plaintiff can bring a lawsuit against a defendant.

A cause of action must include a legally recognized harm or injury caused by the defendant’s actions or failure to act, as well as the necessary elements to establish liability, such as duty, breach, causation, and damages.

Common types of causes of action include breach of contract, negligence, fraud, and violation of statutory rights.

What makes up a cause of action?

In an effort to avoid legalese, think of a cause of action as a ticket into the courtroom. It’s what a plaintiff must present to the court to say, “Here’s why I believe I’m entitled to some form of legal relief.” Without pleading a valid CoA, you won’t get very far in the process. 

The cause of action starts with two main ingredients: a legal theory and a set of facts. The theory is your legal basis for seeking relief; it’s the rule that you believe has been violated.

The set of facts, on the other hand, is your story. It’s the specific events that occurred that you claim have infringed upon your rights or caused you harm.

Let’s break those down a bit:

Legal theory

Your legal theory is the backbone of your CoA. Whether it’s a breach of contract, negligence, or any other legal violation, your theory must have some basis in statutes or common law.

In California, some legal theories are so common that the court system actually provides form complaints to help litigants properly plead their CoA. As mentioned prior, some examples include breach of contract, general negligence, products liability, and motor vehicle negligence.

That said, the list of legal theories that form the bases of California causes of action is long. So, if you don’t find yours among California’s prepared forms, don’t give up. Somebody, somewhere, has probably sued someone using the same CoA you wish to assert. (See the last section of this article for more on that).

Statement of facts

It’s one thing to have a solid legal theory, but the facts are what breathe life into your CoA. In fact, the California Code of Civil Procedure requires that litigants plead a “statement of facts constituting the cause of action, in ordinary and concise language.” (Emphasis added). 

The italicized portion of the statute is important. You don’t want to give the court a long-winded recitation of facts that includes extraneous details. Rather, you just want to tell them what they need to know in order to determine whether your lawsuit can proceed. 

This means your facts should address each element of your cause of action. Elements, of course, are the necessary components of a particular claim. For a breach of contract CoA, for example, you’d need to lay out facts showing:

Note that this is one area where California practice varies substantially from Federal practice. While Federal courts generally only require notice pleading (i.e., giving just enough detail to let the defendant know what your lawsuit is about), California is a fact-pleading state.

That means your complaint needs to assert specific facts that, if proven, would result in you winning your case.

The importance of getting it right

Even though California has fairly generous policies when it comes to amending complaints, the importance of adequately pleading the elements of your cause of action cannot be overstated.

Indeed, a meticulous approach to drafting CoAs is not just about adhering to procedural formalities; it’s about avoiding costly delays (at best) and having your case dismissed (at worst). 

Specifically, poorly drafted CoAs are the gateway to a demurrer, a procedural challenge that can derail your lawsuit before you and your client ever set foot in a courtroom. Let’s talk about that risk for a moment, shall we?

Understanding the demurrer

A demurrer serves as a sort of bouncer in the California legal process. A demurrer is a responsive pleading that objects to your complaint and asks the court to throw out your lawsuit. And, in case you’re wondering, “failure to state facts sufficient to constitute a cause of action” is one of the chief bases for a demurrer.

In essence, it is the defendant’s first opportunity to scrutinize the sufficiency of the allegations stated in your complaint. By filing a demurrer, the defendant is asserting that, even if everything you’ve claimed is true, your causes of action cannot possibly survive.

And even though demurrers to complaints are rarely favored by California judges, (a) they do cause delays in your case (which always come with costs to your client), and (b) they can give an early signal to your judge that you’re not a careful practitioner.

Indeed, drafting a cause of action that withstands a demurrer’s test isn’t merely about avoiding dismissal; it’s about affirming the legitimacy and seriousness of your legal endeavor.

A well-constructed CoA serves as a testament to the credibility of your client’s grievances, and reinforces the narrative that their claims are worthy of the court’s attention and, ultimately, relief.

Common pitfalls to avoid

Let’s boil all of this down to some cold, hard advice on drafting adequate CoAs. More particularly, let’s begin by recapping what not to do when trying to draft causes of action that will survive a demurrer:

Hot tip for drafting a bulletproof CoA

One of the best tips I ever got when it comes to drafting demurrer-proof CoAs was handed to me by an older attorney when I was in my first year of practice. When I initially heard his advice, I thought perhaps he’d lost his mind.

“Go look at the jury instructions,” he said.

“Jury instructions?” I thought to myself. “We haven’t even filed the complaint and this guy wants me preparing for trial? That’s preposterous!” 

Oh, how wrong I was.

Once I overcame my young attorney bravado (and after scratching my head over how to draft the complaint for a couple of hours), I followed his advice. And guess what I found? Everything you need to draft the perfect CoA is right there in the California Civil Jury Instructions

Let’s say you’re drafting a complaint for breach of contract. Well, Jury Instruction 303 is literally titled “Breach of Contract – Essential Factual Elements.” 

He was right! Everything I needed to allege (and eventually prove) was laid out in black and white.

The instruction read something like this:

To recover damages from Defendant for breach of contract, Plaintiff must prove all of the following:

  1. That Plaintiff and Defendant entered into a contract;
  2. That Plaintiff did all, or substantially all, of the significant things that the contract required;


  1. That Plaintiff was excused from having to [specify things that plaintiff did not do, e.g., obtain a guarantor on the contract];
  2. That [specify occurrence of all conditions required by the contract for Defendant’s performance, e.g., the property was rezoned for residential use];


  1. That [specify condition(s) that did not occur] [was/were] [waived/excused];
  2. That Defendant failed to do something that the contract required;


  1. That Defendant did something that the contract prohibited;
  2. That Plaintiff was harmed; and
  3. That Defendant’s breach of contract was a substantial factor in causing Plaintiff’s harm.


Understanding the legal definition of a cause of action is essential for legal professionals, especially in the California judicial system, where precise and effective drafting can make or break a case.

Properly structuring and pleading causes of action not only enhances the chances of a successful lawsuit but also demonstrates competence and professionalism.

By avoiding common issues such as lack of specificity, overloading information, and misunderstanding the exact legal definition and application of a cause of action and other legal bases, practitioners can craft robust causes of action that withstand procedural challenges.

That’s it, folks. All you have to do is fill in the factual details and, Voila! You’ve got yourself a bulletproof cause of action. It’s not the equivalent of legal rocket science, but it is important to spend the time to do it right. 

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