Q: Federal cases can be consolidated only with federal cases?

A: Federal cases are typically consolidated within the federal court system, as governed by the Federal Rules of Civil Procedure. This means that for consolidation to occur, the cases in question must all fall under federal jurisdiction. Consolidation is generally used to streamline cases that involve common questions of law or fact to promote judicial efficiency and consistency in rulings.

Coordination between federal and state cases, such as those in California, is more complex. While a direct consolidation of state and federal cases is not typically possible due to jurisdictional differences, there can be a degree of coordination. This can occur through techniques like staying proceedings (temporarily halting a case) in one court while a case with similar issues proceeds in another court, or through judges informally communicating to manage related aspects of cases proceeding in different jurisdictions.

The coordination is often guided by the principles of comity and federalism, ensuring that both federal and state courts respect each other's jurisdiction and authority. Judges in both systems are mindful of parallel proceedings and strive to avoid conflicting judgments.

For cases involving both state and federal legal questions, sometimes a federal court may apply state law to certain aspects of the case, or vice versa, as appropriate. This is especially common in diversity jurisdiction cases or cases involving state laws but brought in federal court due to the parties' diversity of citizenship.

In such scenarios, it's vital to understand the complex interplay between state and federal legal systems and to strategize accordingly. This often requires careful legal analysis and planning to navigate the jurisdictional challenges and to effectively advocate for your interests in both state and federal courts.