Unless a person is in the legal custody of a psychiatric ward, it is illegal in Sweden to administer sedative injections if the person doesn't agree to it.
Lars-Håkan Nilsson, a medical adivser for the Prison and Probation Service said that the injections clearly broke the rules.
"That's not allowed," he said. Nilsson didn't rule out that the police would be notified about the incidents.
The investigative news program Kaliber examined 33 reports about deportations which occurred from 2010 to 2014. They found seven instances in which deportees were given sedative injections. They were described in the reports as "aggressive" or at risk for harming themselves or others.
Swedish deportations are to be carried out in a "humane and dignified manner," the news report states.
The drug used for the injections, Stesolid, is classified as a narcotic. The report says that four of the injections were given against the deportee's will, and two just before the deportee's plane took off.
The Swedish Prison and Probation Service is responsible for tranporting deportees.