I assume if you have a look at his statements there will be past instances of this, and in fact yes a crime has been committed, some one has attempted to remove funds from another’s account, even if they were not successfully its still a crime. Bank will change is bank AC number, cards etc, suggest he gets rid of his check book, he has no need for it as he/ you can just use a debit card! I have seen this at work, these people get jobs in care homes for this reason!