Forensic Scientist

• A forensic scientist collects and investigates physical evidence such as blood, fingerprints, saliva and drugs. He also reconstructs crime scenes, completes reports, prevents anyone from tampering with the evidence and testifies in court. A degree in justice studies helps the person learn about violent crime and ethics. Forensic science requires you to have a bachelor's degree in chemistry, biology, genetics or physics. A forensic scientist earns from $35,000 to $50,000 per year as of 2009, according to Criminal Justice USA.
  
  

Mental Health Counselor

• A mental health counselor helps people who have problems such as addictions, family problems and domestic violence. She then comes up with techniques to help them deal with their problems. This person keeps records on clients based on interviews, observations and evaluations. Mental health counseling requires you to have bachelor's and master's degrees in psychology or sociology. Some states also require a license to practice counseling. A degree in justice studies gives this person a background in human and societal behavior. The salary for a licensed mental health counselor ranges from $32,803 to $45,000 per year as of December 2010, according to Payscale.
  
  

Criminal Defense Attorney

• A criminal defense attorney represents an individual who is charged with a crime. The attorney studies the evidence the government has against his client. He has to persuade the jury that his client isn't guilty by presenting his own case or raising questions about the prosecution's case. A criminal defense attorney can have a bachelor's degree in English, history or criminal justice. He must pass the Law School Aptitude Test (LSAT) to attend law school. A criminal defense attorney must know all about the legal system. A bachelor's degree in justice studies provides this background. The median salary for a criminal defense attorney is $94,930 per year, according to State University.
  
  

Police Detective

• A police detective solves crimes. She works on cases including rape and murder. The police detective collects evidence from the crime scene. She also follows suspects and interviews their friends and family members. The detective can also arrest the suspect once she's got enough evidence against him. Police departments sometimes require detectives to have a bachelor's degree. A detective with a bachelor's degree can start out with a higher salary. For example, a detective's starting salary is $56,898 per year at the Los Angeles Department, according to Education Portal.