1. Legal assisted suicide encourages people with years to live to throw away their lives. See: Nina Shapiro, "Terminal Uncertainty": Washington's new "Death with Dignity" law allows doctors to help people commit suicide - once they've determined that the patient has only six months to live. But what if they're wrong? The Seattle Weekly, January 14, 2009, https://choiceisanillusion.files.wordpress.com/2013/10/terminal-uncertainty.pdf
2. Legal assisted suicide is a recipe for elder abuse, for example, in the inheritance context. See this short bar article (non-lawyers say they like it): https://www.kcba.org/newsevents/barbulletin/BView.aspx?Month=05&Year=2009&AID=article5.htm
3. Once assisted suicide is legal, there is pressure to expand to euthanasia for non-terminal people, for example, to you or your family member, who through no fault of their own, falls on hard times: http://www.montanansagainstassistedsuicide.org/2014/10/this-is-how-society-will-pay-you-back_9.html