An Australian mother convicted of killing her children claimed a “victory for science” on Tuesday after an unexpected research breakthrough helped win her freedom after 20 years in prison. Kathleen Folbigg was jailed in 2003 after she was convicted of killing her four infant children, who died separately without explanation between 1989 and 1999. She was found guilty despite a lack of forensic evidence linking her to the deaths and steadfastly maintained her innocence during her 20-year incarceration. Scientific breakthroughs in recent years have uncovered genetic mutations that helped explain why some of the children died, paving the way for Folbigg to be released from prison on Monday. “I’m extremely humbled and extremely grateful for being pardoned and released from prison,” Folbigg said in her first public statement since being released. “Today is a victory for science and especially truth.” The 55-year-old also said in a short video message she would grieve for her children “forever”, and “missed them and loved them terribly”. Folbigg was pardoned by New South Wales Governor Margaret Beazley after a long-running inquiry concluded there was “reasonable doubt” she had killed her children. Although she has won her freedom, Folbigg must now go through a separate legal process to have her convictions officially overturned. Folbigg’s lawyer Rhanee Rego said Australia’s court system had “failed her at every step”, and it had taken authorities far too long to reopen the case.