It sounds like your father is a federal employee or contracts in this space. Cannabis is still not legal federally and doing what you propose exposes him to a problem should it come to pass.
I would refrain from doing anything that places him in peril of losing his job. If that happens and he can no longer pay his end of the mortgage, assuming there is one, or taxes, expenses, etc on the house then this affects you as well.
There is no law that will hold him harmless. It would come down to what an administrative judge believes is fair. So while I highly doubt anyone will ever even know about it should they find out and he get in trouble the chance that he will pay a price exists.
I think in fairness you should continue to buy your weed as usual and not chance it.
This is only my opinion of course.
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