Hello. There is a sort of evidence known as 'circumstantial evidence' which may be the type of proof that serves as the basis for your brother's arrest. Your brother is considered innocent unless and until proven guilty and the standard of proof is proof beyond a reasonable doubt. Your brother needs attorney representation (from an attorney licensed in the involved state). Some attorneys are available seven days for emergency legal needs. Many attorneys will confer initially at no charge. Then, if legal work is performed, some attorneys will provide a reduced fee for financial hardship. Some attorneys may also assist you in limited scope manner to conserve legal costs. All the best.