Legal Question in Real Estate Law in California

Fix your caps lock key. You can't serve a lawful subpoena without a pending case. You can, however, sue John Doe and subpoena craigslist.org for their IP address, and you can then subpoena the internet service provider that owns that block of IP addresses for the name and address of their subscriber. Then, when you determine the identity of the ISP subscriber, you file an amendment to your civil complaint to substitute the villain's real name for that of John Doe.

The first part of what Mr. Stone said was correct - the part about your caps lock key on your keyboard. The second part was not correct. No one can issue a subpoena without a pending court case, but if you are not an attorney, you couldn't issue a subpoena without apply for the court to issue one on your behalf. So you have to have a court case, no matter what.

Certain official bodies can issue subpoenas without a suit pending, such as a grand jury or Congress. You and I can't.

I haven't heard of suing a John Doe defendant without naming at least one non-fictitious defendant. Perhaps that can be done, but I'd want to research it first. I'd be concerned that it could be an abuse of process.