Many leftist individuals and groups like to use the acronym ACAB as a slogan. It stands for “All Cops Are Bastards” and, obviously, expresses disdain for the police. Similarly, purported pacifists and anti-militarists use the slogan “Soldiers Are Murderers” (which appears to be more common in German-speaking countries).
Both slogans are strong, generalized statements. As such, they label an entire group of people and, by their internal logic, do not allow for any exceptions. This is the basic reason why these and similar slogans are not just factually wrong, but actually advance goals counter to those of the people most commonly using the slogans.