The southern black codes: a. were denounced by president johnson and declared unconstitutional by the supreme court. b. were some of the first laws adopted as part of radical reconstruction in 1867. c. allowed the arrest on vagrancy charges of former slaves who failed to sign yearly labor contracts. d. northerners because they saw that the rule of law was returning to the south. e. allowed former slaves to testify in court against whites and to serve on juries.