The trumpet was used by members of a police union in a general public sector strike on April 18, 2012. The strike stoped and restricted work across the country in education, science and culture, health and social care, among professional firefighters and police employees. About 100,000 civil servants have gone on strike against proposed government saving measures.

The strike is also one of many different types of demonstrations documented by photographer Tone Stojko over the past fifty years. An insight into his photographic opus of demonstrations will be on display on the platform in front of the museum in October. A more extensive set of Stojko's photographs will be presented in the monograph "Our anger is boundless"  Demonstration 1968-2020.