Photography of lease violations

[Carl Mathis]

I own a house with a second structure on the property, a garage with attached finished room. The lease very clearly states that the garage and room are not included. When I discovered the tenants had been using it I informed them in writing that they need to stop and, "Do not enter or use in any way" including a reference to the clause in the lease excluding this structure. Despite this they continue to use it.

They have become an ongoing problem and I want them out - my attorney says this trespassing issue is the best one to stop them dead in their tracks since it is both a lease violation and breaking the law. The issue I am wondering about is this: I have no evidence of their current use and they have become so adversarial that visiting on a pretext then snooping around won't work. What will work is having a 3rd party keep an eye on it and take some pictures. With this I have metadata date/time and photos of them in the forbidden structure.

I am wondering about the legality of such observation. It is my property, one can observe from the street that they enter and stay in the other structure. It would seem that any private citizen could take such a photo, certainly the property owner, especially as evidence of a crime and lease violation.