How can you find out if a member of your family has taken out a life insurance policy on a now deceased family member before they passed away without their knowledge or by having them sign said papers?

As far as I know, the Named Insured on a Life Policy must at least sign the application in order for it to be issued. Did the deceased know about this Life Policy. If not, there's a monkey in the woodpile somewhere. I know of no legal manner in which to discover the actual facts. The Beneficiary would be required to provide a formal death certificate along with surrendering the policy in order to colledct. The only way you can find out is to confront the person...any other way would be a shady deal, like if you tried to get someone in that person's bank to tell you if such a deposit had been made; or snooping in the individuals files in their home or office....which I suggest you do not do!