Police arrested a man for sexual assault Tuesday afternoon.  According to the police report, Christopher Gibson, 35,  of Sedalia was taken into custody on a warrant issued in mid-August.  Gibson allegedy assaulted a woman while walking on Sixth Street in downtown Sedalia on July 31st.  In his statement, Gibson claims he rolled an ankle and put his hands out to catch himself, touching the woman on the shoulder.  He is being held on a $5,000 bond.