Masks in schools took center stage in federal court in Denver Monday, with lawyers for the Douglas County School District asking a judge to halt a mask exemption policy passed earlier this month by the county’s newly formed public health department. U.S. District Judge John L. Kane didn’t immediately rule on the request for a temporary restraining order but told everyone to be back in his courtroom Tuesday morning to wrap up arguments. The 64,000-student school district sued the Douglas County Health Department last week on behalf of nine families with children with disabilities, who claim their kids’ civil rights under the Americans with Disabilities Act are being violated by the mask exemption. Their children have health conditions like asthma, cystic fibrosis, epilepsy, diabetes and Down syndrome that make them more susceptible to more severe illness, or death, should they contract COVID-19, the suit claims.