Instead of levelling accusations in a lawsuit, DLA Piper partner Vanina Guerrero this week used an open letter to detail her sexual assault allegations against the co-head of the firm's Silicon Valley office.

In the letter, she asked the firm's leaders to voluntarily release her from a mandatory arbitration provision, asserting that no lawyer "should be forced to litigate claims involving sexual assault and battery or sexual harassment by male lawyers in secret".

Airing such allegations in a letter may raise eyebrows, but it is not an unusual tactic for clients of Wigdor LLP, which is representing Guerrero. Other clients of the New York-based employment firm have written open letters calling on companies to release them from arbitration, from Charter Communications, Ernst & Young, Morgan Stanley and Uber Technologies.