Staff members at a Richfield nursing home are accused of forging a do-not-resuscitate directive after responding slowly to a patient dying, according to police. In a search warrant affidavit filed Tuesday in Hennepin County District Court, police asked for a judge’s permission to seize from The Villas at Richfield all relevant medical records, video surveillance and identities of any medical staff involved in the care of 55-year-old Candace Columbus, who died Oct. 2.