Jan has twice been named by the Daily Journal, the State’s Legal Daily newspaper, as one of the Top 100 Women Litigators in California. Since 2005, she has consistently been identified as a Super-Lawyer, selected by peers as being in the top 5% of lawyers in Southern California. Jan has practiced environmental law since she graduated from UCLA Law School in 1971.

For the first twenty-one years of her practice, Jan worked in various public law offices. In 1995, Jan opened her own public interest oriented environmental law practice, known as Chatten-Brown & Carstens. Along with four other attorneys, Jan primarily represents environmental and community groups. Much of the practice involves litigation under CEQA, and Jan has appeared on many panels on CEQA. She has also taught environmental law at UCLA and USC law school. In addition to being the current President of PCL, Jan has served as the President of California Common Cause, the Sierra Nevada Alliance, and been extensively involved in a number of other environmental and public interest organizations and boards.