On 12 March 1948, Charles McLean, John Denis Teahan and Isabella Jane Johnston were appointed Royal Commissioners to the Royal Commission on Betting.

The Royal Commission's terms of reference were to inquire into and report upon:

1) The best means of controlling and minimising betting on horse racing;

2) To what extent, in what form or forms (other than by the licensing of betting shops), and subject to what controls and safeguards it is expedient that such betting should be permitted or prohibited by law;

3) The use of totalisators;

4) What should be done, by legislation or otherwise (a) to minimise or restrict those factors which tend to stimulate such betting, and (b) to stimulate those factors which tend to discourage such betting;

5) If any control authority be recommended, what should be its nature, functions, powers and duties, and how it should be financed;

6) What legislation would be necessary in order to give effect to the Commissioners' recommendations, and what other alterations, including alterations to penalties, should be made to the State's betting laws;

7) If effect be given to the Commissioners' recommendations, what advantages and disadvantages are likely to result; and

8) Any other matter in relation to such betting into or upon which the Commissioners, with the concurrence of the Hon. Attorney General for this State, consider it desirable to enquire and report upon.