You esentially have to two options. First, if you don't want to pay the bill, you will need to report this as identity theft to the carrier, who will then either itself report it to the police or expect you to report it the police. The *only* way to avoid responsibility for the bill is to claim that someone--your brother--stole your identify and ran up the charges w/out your permission.Otherwise, if you don't want to do that, you'll be responsible to the phone carrier. To avoid damage to your credit and/or you ability to receive telephone (or other services, such as internet) services from the carrier, you will need to pay the bill. You can then bring a civil suit against your brother to recover the money.