BackgroundIn Norway, it is usually GPs that refer patients to involuntary admission. A high proportion of such referrals come from out-of-hours clinics. Little is known about who first initiate the contact between the patients and the referring doctors and which expectations the referring doctors have with respect to the involuntary admissions. The aim of the study was to examine who first detected the patients who were subsequently involuntarily admitted, and to examine the referring doctors’ expectations for the admissions.MethodsSemi-structured interviews with 74 doctors that had referred patients for involuntary admission at a psychiatric hospital.ResultsPatients who were involuntarily admitted were detected by other branches of the health service (52 %, n = 39), family (25 %, n = 19), and the police (17 %, n = 13). The doctors mentioned these expectations for the admission (more than one expectation could be given): start treatment with neuroleptics: 58 % (n = 43), take care of the patient: 45 % (n = 34), extensive changes to the treatment regime: 37 % (n = 28), solve an acute situation: 35 % (n = 26), and clarify the diagnosis: 22 % (n = 17). Female doctors significantly more often expected that the patients would be examined and treated, while the male doctors significantly more often expected that the patients would be cared for.ConclusionsInvoluntary admissions are typically complex processes involving different people and services and patients with various needs. More knowledge about the events preceding hospitalization is needed in order to develop alternatives to involuntary admissions.Electronic supplementary materialThe online version of this article (doi:10.1186/s13033-016-0048-8) contains supplementary material, which is available to authorized users.