A native of Rathfarnham, she competed at the 2012 Summer Olympics in the Women's Laser Radial class. She won her first four days of sailing at the London Olympics and, on the fifth day, came in 8th and 19th position. On the sixth day of sailing she came 2nd and 10th and slipped down to second, just one point behind the Belgian world number one. She was a very strong contender for the gold medal but in the medal race she was overtaken on the final leg by her competitors and finished in 4th, her personal best at a world class regatta. Murphy won her first major medal at an international event when she won gold at the 2013 European Sailing Championship.