Yes, Black Panthers such as George Jackson contribute positively to African-American civil rights. While MLK's attempts at non violent protest were undoubtedly a positive contribution, a lot of things didn't change for the better until the United States was faced with a militant civil rights group that was ready to crack heads.
Groups like the black panthers ended up being more racist than the whites ever were. What good does it do to combat someone being racist by being racist right back to them. These groups did not help African American civil rights, and actually caused more racism towards their minority group.
No, Black Panthers such as George Jackson do not contribute positively to African-American civil rights, because they rule by threat and intimidation. The Black Panthers even pace outside of polling stations on occasion. They plan to marginalize other races by using force. This is the exact same thing that they accuse other ethnic groups of doing.
While I understand the anger that spawned the Black Panthers, they do not contribute positively to the progress of racial equality in this country. Quite the opposite, they confirm the fears of those with racist views that think blacks are a bunch of scary thugs that cannot be trusted with anything. They are counter-productive to civil rights.
I do not think that Black Panthers such as George Jackson contribute positively to African-American civil rights. It is unfortunate but true. I think that they are too angry and somewhat violent to be able to make a positive contribution. I do understand their anger but there are better ways to go about it.