Thank you for that great feedback. I only stayed the night at my friends place and i returned home and haven't gone back to my friends place. I don't think the letter would be needed in any case?
I also contacted my local police department, they said charges can be pressed only if it was a dangerous situation and if I was reported missing (which I was not reported). I am a bit paranoid but it is only because my friend's family does not deserve to have charges put against them.
Under those circumstances, I agree with the police you consulted & not the caseworker - a prosecution is very unlikely.
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