Amy Schumer. (Photo by Jamie McCarthy/WireImage) Amy Schumer has promised to take a public stand on gun violence following the deadly shooting during a screening of her film “Trainwreck” last month. John Russell Houser shot two women dead at the Grand Theatre in Lafayette, Louisiana, before turning the gun on himself, and shortly after hearing the horrifying news, Schumer took to Twitter.com to share her condolences. She wrote, “My heart is broken and all my thoughts and prayers are with everyone in Louisiana.” On Saturday, Schumer responded to an open letter aimed at the actress and written by Sarah Clements, whose mother survived the 2012 deadly shooting at Sandy Hook
