I would be glad to share my thoughts and some advice on this subject with you. I will address your question assuming that you are still in high school.
My first piece of advice is definitely enroll in college and get your Bachelors Degree in Criminal Justice. Whether you go to a 2 year college first and get an Associate degree in Administration of Justice than to the 4 year college for 2 years to get the Bachelors in Criminal Justice does not matter, but get the Bachelors degree. I'll tell you why. At some point in your police officer or detective career, you may want to advance to an administrative position and this will greatly be in your favor to have the Bachelors Degree. It may also help with promotions as a police officer. So that is step one.
Step two, become a police officer following all the required training your town requires. Than you'll have to actively work as a police officer. In order to be promoted to detective, you will have had to be promoted within your police officer rank. It is usually about 4 or 5 years working in your promoted rank as a police officer that you than can then take a written test for detective. This is another reason why your Bachelors degree will help. Some police depts. require some detectives to have a certain number of hours of college courses. You will have to go for more training focusing on detective work that the department you work for would inform you of.
Sounds like you have a wonderful plan for your career and I do hope that this has been of some help. Best wishes to you in school and for a successful career !
If at this time you are not a police officer, ask this and other career advancement questions during your initial training.
Stay safe and thank you in advance for your service.
What I mean by points...is everyone gets points for longevity/ seniority (the longer you stay the more points you get. If you go back to school for a degree, you get more points. Then when you do test for advancement, those points, plus your score, will increase your chances of getting that promotion. I've seen people ace the tests, but not get promoted because they didn't have the points to increase their position on the list of possible promotion. So that degree will help. But take your time getting your degree.
Most people go to the police Academy or Detention Officer Academy right out of high school...and make it a career...over 20 years with the agency. But if your goal is Detective...get your basic years in and once eligible, you can start on the testing path for that change.
Being a Detective is cool, but you have to work your way to Homicide. This means you will have to work property crimes, narcotics and possibly Sex Crimes before you get to Homicide. But use your time in those areas to learn and improve your skills.
I know you can make this happen and I will be sending you positive thoughts for a successful outcome. Best of luck to you in your endeavors.
James recommends the following next steps:
A college degree can also help immensely in case law, search and seizure (you will be doing a lot of writing (affadavits for warrants) if you make detective), interviews, crime scene analysis, chain of custody, evidence collection....the list goes on. Do not stop taking courses/classes when you graduate academy. I would recommend getting past your probationary period before you start looking to continue your education, especially if your are working in a large city.