Following the Oct. 8 Ebola death of Thomas Eric Duncan in a Dallas hospital, TIME asked Professor Robert Field whether the federal government can restrict the travel of, and even quarantine, those at risk of Ebola exposure, like the health care workers who treated Duncan.

In the Oct. 18 article in TIME, Field field said that federal directives could technically trump state decisions on whether to isolate or quarantine individuals but "[i]t would be an unusual situation in which the federal government wanted to quarantine someone and a state did not."

Field also commented that the Americans With Disabilities Act would traditionally restrict airlines from preventing someone suspected of Ebola exposure from boarding a plane.  However, "there are exceptions for someone who presents direct threats involving something like an infectious disease. An airline could use that exception to deny someone access to a plane," Field added.  

In the midst of the controversy, others have questions whether Ebola samples being studied in labs in the U.S. are at risk of theft.  In a Oct. 22 article in TIME, Field quickly allayed those concerns arguing that it would be highly unlikely for someone to steal Ebola from a lab and convert it to a bioterror weapon.  Risk of theft is low because "stealing an Ebola sample would be extremely dangerous because the thief would face a significant risk of exposure," Field said.

Robert Field is a nationally recognized expert in health care regulation and its role in implementing public policy.