Local Government Code §102.009

(a) The governing body of the municipality may levy taxes only in accordance with the budget. (b) After final approval of the budget, the governing body may spend municipal funds only in strict compliance with the budget, except in an emergency. (c) The governing body may authorize an emergency expenditure as an amendment to the original budget only in a case of grave public necessity to meet an unusual and unforeseen condition that could not have been included in the original budget through the use of reasonably diligent thought and attention. If the governing body amends the original budget to meet an emergency, the governing body shall file a copy of its order or resolution amending the budget with the municipal clerk, and the clerk shall attach the copy to the original budget. (d) After the adoption of the budget or a budget amendment, the budget officer shall provide for the filing of a true copy of the approved budget or amendment in the office of the county clerk of the county in which the municipality is located.