A State of Washington appellate court ruled that a single member LLC must be represented in a court proceeding by a lawyer rather than the sole member of the LLC.  The court said:

A limited liability company (LLC) must be represented by a lawyer in order to litigate. This is simply an application of the general rule prohibiting laypersons from representing other persons or entities in court proceedings. Because a layperson does not have a lawyer’s professional skills or ethical responsibilities, such representation imposes undue burdens on opposing parties and the courts. These considerations are just as important when the LLC has only one owner. We affirm an order requiring the appellant LLC to obtain legal representation in order to pursue its claim”

Arizona LLCs, corporations and partnerships must also be represented in court by a licensed Arizona attorney.

The case is Dutch Village Mall vs. Raymond J. Pelletti, Washington Court of Appeal, Division One, July 5, 2011.