He was admitted to the California bar and to practice before the federal Ninth Circuit Court of Appeals in January, 1964. He became a member of the bar of the United States Supreme Court in 1969.
From 1964 to 1972 he was a deputy attorney general in the Sacramento office of the California Attorney General where he represented the State of California in criminal trials and appeals including death penalty cases before the California Supreme Court. In 1972 he was named head of the Attorney General’s San Diego office criminal division and in 1983 became Chief Assistant Attorney General in charge of the Attorney General’s criminal division statewide.
In 1983 Governor Deukmejian appointed him to the San Diego County Superior Court. There he served in the court’s civil, criminal, law and motion and juvenile departments. In July 1985, Governor Deukmejian elevated him to the Court of Appeal as presiding justice. The voters of the State of California elected him to a full term in 1986 and reelected him to a second full term in 1998.
Presiding Justice Kremer chaired the Judicial Council’s Committee on Criminal Trial Delay Reduction and the Council’s Library Technology Committee. He was later named a member of the California Judicial Council, the policy making body for California’s courts. While a Council member, he chaired the Judicial Council’s Rules and Forms Committee and was co-chair of California’s first Court Technology Committee. Justice Kremer chaired the Task Force on Court Facilities, a body created by the Legislature and charged with evaluating every courthouse in California and recommending steps necessary to bring deficient sites up to acceptable standards. In 2002, Justice Kremer received the Judicial Council's Jurist of the Year award.
Presiding Justice Kremer has been active in legal education through programs for the California Judges Association, San Diego law schools and a variety of lawyer and civic groups.
Presiding Justice Kremer and his wife Kathryn were married in 1964. They have two sons