Illinois DUI lawyers are often asked about statutes of limitations. A statute of limitations restricts the time in which the state can charge you. In that connection, there are two separate but related issues.
If you are accused of a misdemeanor (fewer than three previous DUI offenses), the state has 18 months from the date the offense was allegedly committed in which to file charges against you. If you have more than two previous DUI offenses, you may have committed a felony DUI. In that case, the state has 3 years from the date the alleged offense was committed in which to bring charges.
Once charges are filed against you, the statute of limitations has been satisfied. Therefore, if you skip out on court, the state can prosecute you for that DUI years later and not run afoul of the statute of limitations.
This should not be confused with the speedy trial rights that are accorded to all persons in Illinois who are charged with a crime. If you are in custody (jail), the state has 120 days to bring you to trial, provided you make a speedy trial demand and provided the delays are not your fault. Missing out on your court dates does not help you mount a speedy trial defense. If you are not in custody, the speedy trial right is 160 days.
If you are convicted of the DUI, either because you are found or plead guilty and do not receive court supervision, or are found guilty because you do not appear in court, your driver's license will be revoked. You must have a hearing at the Illinois Secretary of State (the Illinois DMV).
This is so no matter how long ago your DUI conviction occurred. The rule applies even if you have had a driver's license in another state for a long time and now the other state will not renew the license because of the Illinois hold on your driver's license.