Avi
Depends on the person and circumstances of the person whose funeral it is. Some you dont have to attend to, but others you must attend otherwise you will be seen and out of touch and inconsiderate. The attack for example in South Caroline at a church, if a frum jew was the mayor of that town there would have been a major outcry if he would not attend such a funeral.
If a police office was killed its another situation where you really must attend the funeral.
If it was just some murder on the street he doesnt need to attend