Mr. Warner began his career with the San Francisco public defenders' office in 1967 and became principal trial attorney in 1969. In 1970 he began his civil trial practice defending medical malpractice lawsuits at Hassard, Bonnington, Rogers & Huber. He was elected partner in 1973.

In 1979 Mr. Warner relocated to the Monterey Peninsula where he limits his referral based trial practice to civil litigation and complex civil litigation matters. Areas of practice include business litigation, professional liability claims, general personal injury, insurance litigation including-insurance bad faith, medical malpractice, and products liability claims.

Mr. Warner has been lead counsel in a number of complex civil litigation actions and has tried over 100 cases. Mr. Warner has also conducted over one thousand private mediations and arbitrations, serves as a special master, discovery referee and judge pro tem for the Superior Court of Monterey County.