Judge Altenbernd was born in Muscatine, Iowa, in 1949. He is married and has two adult daughters. He graduated from Muscatine High School in 1967. During his teenage years, his father taught him carpentry, and he worked in that trade until becoming a member of the bar. He attended Harvard College from 1967 until 1969. After volunteering for a year with the Delta Ministry in Greenville, Mississippi, he returned to the University of Missouri where he received his B.A. degree, with honors, in psychology in 1972, and became a member of Phi Beta Kappa. He received his J.D. degree from Harvard Law School in 1975, and a Master of Laws in Judicial Process in 1998 from the University of Virginia.
Following law school, he entered private practice in Tampa with the law firm of Fowler, White, Gillen, Boggs, Villareal & Banker, P.A. He became a partner in that firm in 1979 and a member of its Board of Directors in 1986. While in private practice, he was a civil litigator and frequently appeared before the Second District Court of Appeal. He was also a member of the Florida Defense Lawyers Association and the International Association of Defense Counsel, and was chairman of the Florida Bay Area March of Dimes.
Judge Altenbernd was appointed to the Second District Court of Appeal on January 3, 1989, by Governor Bob Martinez and retained by the electorate in 1990, 1996, 2002, and 2008. He served as chief judge of the court from February 2003 to June 2005, and served as president of the Conference of District Court of Appeal Judges in 2006 and 2007. He was named Jurist of the Year by the Florida Board of Trial Advocates (1998) and by the Florida Chapter of the American Academy of Matrimonial Lawyers (1999); was awarded the James C. Adkins Award from the Appellate Practice and Advocacy Section of The Florida Bar (2002); and has served on many supreme court committees, including service on the Committee on Standard Jury Instructions in Civil Cases (1992-2004).
He is the Florida liaison for the American Inns of Court and a member of both the Cheatwood Inn of Court and the Jacob Criminal Appellate Inn of Court. In 2010, the American Inns of Court awarded him the A. Sherman Christensen Award. He was a trustee of the Conn Memorial Foundation between 1998 and 2011. He is an Eagle Scout who currently serves as Scoutmaster for Troop 100 at Academy Prep of Tampa.
Publications include: "Briefly State: The True Confessions of a Legal Grease Monkey," The Record, Journal of Appellate Practice & Advocacy Section, The Florida Bar, Vol. III, No. 1, p.9 (Apr. 1995); "Living with Dr. Canakaris in the Ivory Tower," The Family Law Commentator, The Florida Bar, Vol. XVIII, No. 1, p.3 (Nov. 1992); Raymond T. Elligett & John M. Scheb, Florida Appellate Practice and Advocacy, The Summary of Argument: Walking in the Court's Shoes" p.171, Book World Publications (1998); "Quasi-marital Children: The Common Law's Failure in Privette and Daniel Calls for Statutory Reform," Florida State University Law Review, Vol. 26, No.2, p.219 (Winter 1999); "Certiorari Review of Nonfinal Orders: Does One Size Really Fit All? Part I," The Florida Bar, Vol. LXXXVI, No. 2, p.21 (Feb. 2012).