An early activist for the liberation of Soviet Jewry, Leibler famously encouraged then-union leader Bob Hawke to advocate for the release of the Prisoners of Zion, Soviet Jews jailed for supporting Israel, during a visit to Russia. Leibler made several visits to the USSR himself and met Jewish dissidents. A group of 15 refuseniks travelled to Australia in 1988 to thank Hawke and Leibler for gaining them their freedom.
