FORT COLLINS, Colo., Dec. 1, 2016 /PRNewswire/ -- Volunteer numbers are rising as organizations that use unpaid workers are drawing on more of them than ever, according to new research from Verified Volunteers' Volunteer Screening Trends and Best Practices Report: 2017. The number of one-time or casual volunteers is also growing. More volunteers are passing through organizations yet fewer are committing for long periods of time. This is almost certainly true at the holidays when organizations typically experience increased volunteerism for tasks ranging from food preparation to toy distribution. Logo - http://photos.prnewswire.com/prnh/20161130/444240LOGO "Unfortunately, you may not know your volunteers as well as you used to," says Katie Zwetzig, executive director of Verified Volunteers. "Eighty-eight percent of organizations we surveyed serve vulnerable populations such as children, the elderly or the disabled. These volunteers should be appropriately vetted and trained. You don't want harm to come to those you're trying to help, and you don't want your organization harmed by reputation or financially by an incident that results in a lawsuit." Sixty-one percent (61%) of organizations say they expect to conduct more background checks in 2017. Legal liability is an organization's biggest risk, according to Zwetzig. An organization is responsible for the actions of its volunteers. If an injury or damage occurs, even if caused by a one-time volunteer, an organization can still be considered negligent in the eyes of the law. Liability can extend to automobile liability, negligence resulting in damage or harm, and dishonesty by fraud, embezzlement or theft. Organizations are more likely to be found liable if prior offenses were not found in a background check.