Fundamental flaws have been identified with one of the Welsh Assembly Government's first attempts at drawing up a new law.
A committee found problems with the measure on education travel
Under the 2006 Government of Wales Act, Wales-only legislation can be created in certain devolved areas.
But a scrutiny committee has found a number of problems with proposals for legislation to improve travel to schools and further education.
These include a basic lack of powers over key issues, such as seat belts.
The enterprise and learning committee's scrutiny report found the new law, known as an assembly measure, would be powerless with regard to vehicle standards, seating arrangements or seatbelts.
The committee also found inadequacies over codes of conduct.
Plug the gap
It found unruly children on public transport would only be covered by a code of conduct if their tickets had been paid, in full or in part, by the local authority.
Those paying themselves would be exempt, and remain beyond the control of the new legislation.
The assembly government will present more detailed proposals in the new year.
But if it fails to request enough powers to plug the gap, the committee has said it may consider bringing forward its own request for extra powers from Westminster.
It wants the assembly government to give further consideration to the code of conduct, including to the issue of who will be covered by it.
The committee also wants the assembly government to give further consideration to the possibility of staggering the opening and closing times of schools.