You have probably heard that you cannot be tried for the same act twice. This is a general explanation of the legal principle of double jeopardy. Note that there are some elements that your case must meet for the double jeopardy defense to apply. For example, to succeed with the defense, you have to prove that:
You Are Facing A Criminal Case
Double jeopardy laws only apply to criminal cases; it doesn't apply to other cases such as civil lawsuits. This means if you have been tried for DUI (driving under the influence) and sentenced to a few months in jail, you can't face the criminal charges of DUI again even if the shopkeeper thinks you got away with a light sentence. However, if it turns out that you managed to damage another person's property during your drunken driving episode, the owner of the property can still sue you for damages. This is because a damages claim is a civil lawsuit and not a criminal one.
You Have Been Charged With The Same Offense
Criminal suspects usually face multiple charges stemming from the same act. Take an example where you have been arrested for DUI and you had a minor passenger at the time of your arrest. In this case, you can be charged with DUI and reckless endangerment of a minor. Now, consider an example where the prosecution errs and only charges you with DUI. In this case, you can face the charge of reckless endangerment of a minor even after your DUI case has been dispensed with; after all, it's a different offense. However, you can't be charged with DUI again because that would violate double jeopardy laws.
You Have Been Charged With The Same Government
Lastly, you can also claim double jeopardy if you are being charged and tried by the same government that tried your earlier case. Your trial will go on if the second charge is from a different jurisdiction. A classic example of this is a case where you have been tried in a state court for drug related offenses. If it turns out that your alleged acts also violated some federal law, then the federal court can still try the same charges; it won't violate double jeopardy laws while doing so.
As you can see, double jeopardy laws are complex and filled with exceptions. This isn't something you can rely on if you are facing a criminal charge. Anytime you are facing a criminal charge, consult a criminal defense lawyer from a firm like St Lucie Criminal Defense Attorney to help you strategize.