Boys are taught never to hit girls from a very young age. There is no such rule protecting boys, specifically, from acts of violence. A male hitting a female is viewed as a loathsome act of cowardice. A female being physically assaulted by a male is especially sympathized with, partially because females tend to be physically smaller and less strong than males. Although gender roles have evolved a great deal, males have traditionally been the protectors of females and the young. In the role of caregivers, and mothers, females are socially deserving of sympathy, respect, and protection from those who would harm them.
Yes, the public sympathizes more with a female assaulted by the police than with a male victim. Women are seen as the weaker sex by many people in society, including women. This means that when a woman is assaulted by a police officer, it is seen as a much more grave crime than when a man is assaulted.
Yes, the public does seem to sympathize more with a female assaulted by the police than with a male victim. Unfortunately, females are still thought of as more helpless and in need of protection than males. However, the public does seem to universally sympathize with any person that is assaulted by the police.
While many of us strive to create a world of equal rights and opportunities, the limits of the female body versus the male (and vice versa) are something that we will probably never overcome. People are definitely going to sympathise more with a female who was assaulted than a male because the man is always perceived as stronger and more of a threat.
If you are to look back at 2016 and 2015, you would see all the riots and protest that ensued when a man is assaulted or even killed by the police force. "Hands up! Don't shoot!" That entire protest spawned when a man was shot and killed by police officers. People still argue and riot over issues like this. It is tragic any time something like this happens, whether it be to a women or a man. What about when a man was chocked and beaten by police? That spawned a huge riot and protest. I'm not going to personally sympathize with one sex or the other. But you really have to consider the facts here.