Saying the 2011 murder of Realtor Ashley Okland in a townhome she was showing was “one too many”, the Des Moines Area Association of Realtors on Thursday unveiled a three-pronged plan to protect real estate agents who often find themselves alone in empty houses with prospective buyers they have never met.

Local real estate officials called the plan unprecedented nationwide. Beginning today, real estate agents can sign a voluntary pledge to not show any home to a stranger without first meeting the person at their office or a public place and asking him or her to submit identification. Realtors also can ask sellers to agree to those conditions when they list their home.