Ivan Milat shot taxi driver decades before murders: brother

Ivan Milat shot a cab driver in a bungled robbery three decades before his notorious murder spree, the serial killer's older brother says.

Boris Milat recounted that his brother, then 17, bragged about the shooting the day after the attack.

Neville Knight was left paralysed after Milat shot him in the back on March 6, 1962.

"As soon as a gun got in the hands of that fool, life changed," Boris told the Seven Network.

He kept the secret for more than 50 years and didn't tell police because "he was too much of a Milat then."

Another young petty criminal - Alan Dillon - confessed to the crime, fearing police would frame his younger brother if he didn't.

Dillon spent five years in Parramatta jail for the shooting.

Milat, who is serving seven consecutive life sentences for the Belanglo State Forest backpacker murders, was never a suspect.