If you have committed a criminal offence, then so has your neighbour. As it happens, there is no criminal offence here.
There is a civil issue but not criminal.
She commits the common law tort of trespass by having her bracket overhanging the boundary.
You commit the common law tort of trespass by leaning over the boundary and removing it.
If you break the bracket deliberately, there is a criminal issue which is criminal damage although if you accidentally damaged it removing it, it is unlikely the police would be interested.
If you trip over the bracket and you injure yourself for whatever reason (I cannot see why you would trip over it if it’s a hanging basket bracket but I can see why you may bump into it) then you have a claim against the neighbour in negligence.
Check your house insurance to see if you have legal expenses cover that would pay for the cost of any dispute.
If not, you cannot beat each other with blunt instruments until such time as the matter resolves itself and you would both be faced with the court action if you cannot resolve it between you.
The bracket simply hangs over the boundary, the neighbour would be absolutely stupid to go to court on this and you may find that an initial solicitors letter from a local solicitor avoids all that need.
Can I clarify anything else for you?
I’m happy to answer any specific points arising from this.
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