Cristhian Bahena Rivera, 24 — facing a first-degree murder charge for killing Mollie Tibbetts — is expected to make his initial court appearance Wednesday at the Poweshiek County Courthouse in Montezuma at 1 p.m.Rivera, who is an undocumented immigrant, led investigators to her body in a cornfield in rural Poweshiek County, investigators said Tuesday during a news conference.Investigators first questioned Rivera on Monday, Aug, 20, Iowa Division of Criminal Investigation Special Agent in Charge Rick Rahn said during a news conference.Rivera faces a charge of first-degree murder, punishable by a mandatory life sentence without the possibility of parole.