Complaints of less favourable treatment by managers were also present, including withholding informal benefits or giving menial work, the study by conciliation service Acas revealed.
Between January 2004 and September 2006, 470 individuals brought tribunal claims where the main allegation concerned discrimination on grounds of sexual orientation. Two-thirds of these were from men.
Where bullying or harassment in relation to sexual orientation was alleged, claimants usually said managers had been complicit in the bullying or had failed to act to prevent it.
The private sector was the worst offender in these types of cases, with 70% of claims made against private firms. “Managers may not deal effectively with problems when they occur. This may be due to a lack of training or support from HR departments,” the report said.
The application of internal grievance procedures may make problems worse where claimants feel the procedures are used to cover up what has happened, the study found.
n Acas is looking for a successor to its chair Rita Donaghy, who steps down in October. The post has a salary of £63,470 for a three-day week, and will be for an initial term of three years.