spam calls that stop

When my phone states potential spam call, or it's from an area code, or phone number I do not recognize or out of country. I simply answer the US phone calls as my local Sheriff's department for any United States calls by saying the name of your county sheriff department how can I direct your call? Trust me, they stop calling after you answer the phone that way. Out of country calls, I say department of homeland security, how may I direct your call. Calls stop within a week nothing.