The State has added a second premeditated murder charge to its case against the founder of right-to-die organisation DignitySA, Sean Davison, it emerged in the Cape Town Magistrate's Court on Friday."We are in a position to add another charge of murder. Needless to say, the charges are provisional and may change," said prosecutor Megan Blows.Davison, 57, was arrested at his home in Pinelands in September for the 2013 death of his friend Anrich Burger, who had become a quadriplegic after a car crash.According to the charge sheet, he "administered a lethal amount of drugs to the quadriplegic deceased" at or near the Radisson Hotel in Granger Bay on November 2, 2013.Davison, who helped his mother end her life in New Zealand, revealed to News24 in 2014 that he had helped Burger to do the same.The second charge is in connection with the death of Justin Varian - who had motor neuron disease - on July 25, 2015. The State accuses Davison of "placing a bag over the deceased head and administering helium with the intent of helium deoxygenation and/or asphyxiation" in Fresnaye.According to a Sunday Times report, Davison said that Varian had begged him for advice on how to die and also had a video of Varian expressing his wish to die.Blows told Magistrate Greg Jacobs that they had made progress in their investigation and were in possession of several statements.News24 previously reported that a search and seizure was done at Davison's home, where he, his wife and three children lived. His phone and laptop were apparently confiscated.'Impeccable reputation'Police are in possession of his South African and New Zealand passports.At his first court appearance, he stated in an affidavit that he had not committed a crime."It is and has always been my contention that I have not committed any offence as alleged in this matter," his lawyer Joshua Greeff read from an affidavit.READ: I have not committed any offence' - euthanasia advocate Sean Davison on murder chargeDavison has an extensive academic career and is a member of numerous professional organisations. He has been a professor of biotechnology at the University of the Western Cape since 2004 and heads up the forensic DNA laboratory there.He helped the Truth and Reconciliation Commission identify the remains of anti-apartheid activists, including the Mamelodi 10.Davison also developed a DNA kit to help identify suspects in gang rapes, a service that was offered free to rape victims. During his bail application, Davison said he had built an "impeccable reputation" over the years and incarceration could destroy his character and everthing for which he had worked.The case was postponed for further investigation.Davison, who is out on R20 000 bail, will return to court on January 29.