Liess ayaa u soo baxday tartanka 200m ee ragga ee ciyaaraha Olombikada xagaaga ee 2012 ee London, isagoo jabiyay rikoodhka Switzerland oo uu ku guulaystay waqtigii FINA B-cut off ee 1:58.13 ee tartanka Yurub
Magaalada Debrecen ee dalka Hungary. Wuxuu la tartamay toddobo dabaalyahan oo kale heerka labaad, oo ay ku jiraan Hsu Chi-chieh oo ka tirsan Chinese Taipei. Liess wuxuu ahaa kii ugu dambeeyay 0.16 ilbiriqsi oo ka dambeeya kan kanada David Sharpe. Liess wuxuu ku guuldareystay inuu u gudbo semi-finalka, maadaama uu kaalinta soddon iyo saddexaad ka galay guud ahaan horudhaca.