A cartoon depicting a firing squad of bureaucrats and media with rifles aimed at US veterans has prompted a powerful congressman to call for an investigation into one of America’s oldest veterans advocacy groups, stoking a debate over free speech for political satire.

Rep. Mike Bost, the chairman of the House Veterans Affairs Committee, has asked VA Secretary Doug Collins to investigate the Veterans of Foreign Wars after the satirical cartoon meant to protest cuts to veterans benefits appeared on T-shirts being sold on behalf of the group, which has about 1.3 million members.

The VFW, which was founded in 1899, says it has used the cartoon in different variations since the 1930s to protest efforts to cut veterans benefits. The most recent version features a pair of men in business suits, labeled “bureaucrats” and “media,” pointing rifles at two veterans in military fatigues, with the the phrase “Honor the Contract” printed below. The phrases “Punishing Service,” “Removing Benefits” and “Waste and Fraud” are included in the image.

The VFW says it rolled the T-shirts on June 30, with the Grunt Style military apparel company handling the sale and proceeds meant to fund veterans mental health and suicide prevention initiatives. The following day, Bost, an Illinois Republican, wrote to Collins and issued a news release criticizing the image.