Mencellator

Okay, it's quite a strange situation, here's the backstory:

My old landlady is falsifing information, and pretending I never rented her room so she gets a business discount (and of course I did). I am gathering all the proof I need to take to court. I recently sent a message through Gmail to her telling her to please stop doing what she is doing, and to leave it alone. Now, would you believe, she took that email I sent to her, edited all the phrases to say stuff like 'I was wrong, I never lived at your house', printed out that email with the header and footer details, and handed it in to the Council.

When I found this out, I burst out laughing. Surely she couldn't possibly think that would work? I have the real email sitting here in my Send box.

So, I need to know what the best strategy is for this, because clearly I have damning evidence, but I need to handle this correctly. I was going to print the email out and take it into Council, but that is just the same thing she did, so it doesn't way up much. It might be better to forward the email to their Inbox first, then go into the Council Office and point it out on their screen. I regret not BCC'ing the email when I had the chance. Do you guys know any other way of handling this? To be honest, I think I've got this in the bag, but if it goes to court I want to make sure I can prove which one is the correct email. Is there anything else I can do, perhaps certified documents, or logged records of my emails?