The Australian High Court declared on Thursday in a landmark decision that the school chaplain programme is invalid because it is not supported by a head of constitutional power.

The ruling was the result of a 2012 challenge raised by Ron Williams, father of six children in Toowoomba. The decision affects more than 400 commonwealth spending programme and could force the Abbott government to initiate a major overhaul of the manner the federal government funds everything, reports The Australian.

In the first challenge by Williams, the High Court declared spending on the chaplaincy invalid, but for the Thursday decision, the court knocked over the scheme.

Williams, who has four children enrolled at the Darling Heights State Primary School, pointed out, "Public schools aren't a place for religious missionaries, with or without government funding. The fact the federal government was funding them was adding insult to injury."

The court said, "The legislation purports to support over 400 Commonwealth schemes listed by the executive - but the Court has confirmed that each of these must be able to be connected to a source of Commonwealth legislative power. For some that might be easy enough. But for many, like the chaplains program, it is apparent that the Commonwealth has been acting beyond its constitutional capacity."

Reacting to the court decision, Prime Minister Tony Abbott said the Coalition wants the school chaplains programme to continue.

He said, "This is a policy that was invented by the Coalition, it was supported by the Coalition, so we very much support it and we want it to continue."

The programme provided funding of up to $72,000 each for 3,700 Australian schools to hire chaplains. In May, another $244 million was allocated for the scheme, spread over four years. It targets to provide chaplains for 2,900 schools.

YouTube/Ron Williams