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John Hemann joined Cooley's white-collar practice after leaving the U.S. Attorney's Office for the Northern District of California, where he was chief of the special prosecutions and national security unit and deputy chief of the criminal division. As partner with Cooley, he will be involved with similar matters to the ones he handled as a prosecutor. He is based in San Francisco.

Ellen Sueda left her role as counsel at Weil, Gotshal & Manges to join Ropes & Gray. With experience handling benefits and executive compensation issues in transactions, investments and litigation, Sueda joins the firm's executive compensation and benefits practice group as counsel in San Francisco.

Greenberg Traurig added two attorneys to its corporate practice in Los Angeles. Both April B. Kim and Homin Lee join as of counsel. Kim previously worked at Morgan, Lewis & Bockius and focuses her practice on transactions such as mergers and acquisitions, project development and finance in the energy industry. Lee previously worked at Paul Hastings and focuses her practice on financing matters and lending transactions.

The Sacramento office of Meyers Nave grew with the addition of former Churchwell White partner Robin Baral as of counsel. Baral will work in the firm's land use and environmental law practice group, where he will advise clients on land use, environmental and water law, and public finance. His environmental law practice primarily focuses on developing permitting strategies for new and emerging technologies.

Retired Alameda County Superior Court Judge Wynne Carvill joined JAMS as a neutral on its San Francisco panel. Before serving as a judge, Carvill spent 25 years as a civil litigator. He has a background in antitrust, business, commercial, class action, employment and construction matters.

David Marion joined Nossaman as partner in the firm's corporate practice group. He focuses his practice on commercial agreements, mergers and acquisitions, compliance and general corporate matters. Before joining Nossamon, Marion was a partner at Shulman Bastian. He is based in Orange County.

Private dispute resolution services provider Judicate West added Rebecca Grey as a neutral. Grey currently serves as a judge pro tem and discovery panelist for the San Francisco Superior Court, settlement panelist for the Marin County Superior Court, day of court mediator for the Alameda Superior Court and mediation mentor for the Contra Costa Superior Court. She also founded the mediation firm Grey Resolution.

Los Angeles-based attorney Todd Maron left Tesla, where he was general counsel, to become chief legal officer at bike-share app Wheels Labs Inc. Before moving in-house to work at Tesla in 2013, Maron was an attorney at family law firm Jaffe and Clemens.

Burbank-based Spanish-language television and radio company LBI Media Inc. brought on Arya Towfighi to head its legal department as general counsel. Before joining LBI, Towfighi was briefly a partner at Hawxhurst Harris. He was also senior vice president and general counsel at Univision Communications Inc., where he worked for 13 years.

Warner Bros. Television Group's Jody Zucker was promoted from general counsel to executive vice president of legal affairs. In this role, which the company just created, Zucker will oversee the legal affairs of all of Warner Bros. production divisions. Zucker began working at the Burbank-based company in 2000 as vice president of legal affairs.

Simpson Thacher & Bartlett announced a group of partner promotions across its offices, including the promotion of Robert Guo in Palo Alto. A member of the firm's private funds practice, Guo advises private fund sponsors on the establishment and operation of private investment funds.