<P> In the Westminster system (and, colloquially, in the United States), a money bill or supply bill is a bill that solely concerns taxation or government spending (also known as appropriation of money), as opposed to changes in public law . </P> <P> It is often a constitutional convention that the upper house may not block a money bill . There is often another requirement that non-money bill - type clauses may not be attached to a money bill . The rationale behind this convention is that the upper house, being appointed or indirectly elected, should not have any right to decide on taxation and public expenditure - related policies as may be framed by the directly elected representatives of the lower house . Therefore, money bills are an exception to the general rule that for a bill to be enacted into a law, it has to be approved by both Houses of the Parliament--the lower house and the upper house . </P> <P> Loss of supply in the lower house is conventionally considered to be an expression of the house's loss of confidence in the government resulting in the government's fall . </P>

The dominant role in passing a money bill is vested in the