At the behest of the Mattie J.T. Stepanek Foundation, in 2013, Barbara Mikulski, a United States Senator from Maryland, sent a letter to US President Barack Obama, wanting to declare July 17 (Stepanek's birthday) a national peace day in Stepanek's honor. In July 2014, Ben Cardin, a junior United States Senator from Maryland, joined Mikulski in introducing a House Resolution (#509), which was approved by the Senate and honors Stepanek's life and peace legacy. In 2017, the city of Rockville, Maryland voted to declare Mattie's July 17 birthday as "Peace Day" at a local level in perpetua, as a statement of support for the National Peace Day Campaign.