The radical republicans’ actions in the post-civil war era represented a clear attempt of one branch of the federal government to encroach on the powers of another branch of the federal government. by 1877, which branch was ahead?

By 1877 the Judicial branch was ahead

Explanation:

Post civil war ear Republican Party representatives were divided in their opinion about the practice of slavery. The factions of the Republicans called Radical Republicans were in support of giving full rights to the African American community.

They insisted on the giving equal opportunity as white and insisted of removing the slavery from south.  Due to the resistance from Radical Republicans, there was shift of power from the legislative branch of federal government to judicial branch of federal government.

The Supreme Court has ordered for certain review on constitution laws which were more white centered policies. This action by the judiciary has brought harmony in the American society in the post civil war era.

i'll just take the points xd