Refusing a chemical test for a first-offense DUI under implied consent laws can lead to significant penalties. If you refuse a breath, blood, or urine test after a DUI arrest, you're likely looking at an automatic license suspension, which can last anywhere from six months to a year depending on the state. For example, in states like California, you'll face an additional 48 hours in jail and mandatory attendance at a longer DUI education program if convicted. Additionally, some states might impose fines or require an ignition interlock device after the suspension period. Refusal can also be used against you in court as evidence of consciousness of guilt, although it doesn't directly prove intoxication. Always consult with a DUI attorney to understand your rights and the specific consequences in your jurisdiction.