Based on what you wrote, you could still become a police officer. However, you will certainly have a red flag or two to overcome. Whether or not you will be able to become a police officer depends on many things. For example, if you've used marijuana too many times, even as a juvenile, some departments won't hire you. If you want to become a police officer, you will have to remember many details of your past such as when you were arrested, dates of tickets, how many times you've used drugs, if you've ever stolen anything, etc. So if you want to apply with some police departments, you should start gathering that information as soon as possible. You sound like you have a good work history. Keep it up.