Legal Insurrection's William Jacobson questioned the legality of Elizabeth Warren's engaging in legal practice from her office at Harvard Law School without having gotten a license to practice law in that state. Now a counter-argument has been offered. Mark Thompson writes at the League of Ordinary Gentlemen:

 most importantly, Professor Jacobson ignores Massachusetts Rule of Professional Conduct 5.5(d), which states that:

"A lawyer admitted in another United States jurisdiction, and not disbarred or suspended from practice in any jurisdiction, may provide legal services in this jurisdiction that...are services that the lawyer is authorized to provide by federal law or other law of this jurisdiction."

The Official Comments to Rule 5.5(d) further elaborate to make explicit that 5.5(d) permits such an attorney to have even a "systematic and continuous presence in [Massachusetts] for the practice of law as well as provide legal services on a temporary basis."

As the cases to which Professor Jacobson has drawn our attention are entirely cases from the federal courts, and indeed appear to be cases lying even outside the jurisdiction of the Massachusetts federal courts, and as there seems to be no allegation that Professor Warren was unauthorized to appear in those cases, the Massachusetts Rules of Professional Conduct appear to explicitly exempt Professor Warren's actions in those cases from the prohibitions on the unauthorized practice of law.

Although it is true that Rule 5.5(d) does "not authorize communications advertising legal services to prospective clients in [Massachusetts] by lawyers who are admitted to practice in other jurisdictions," merely listing the location of one's office in an official court filing in which one is properly authorized to appear cannot possibly be construed as a "communication advertising legal services."  

So far, Professor Jacobson has not posted his response. Meanwhile, the story has now hit Fox News.

Update: excerpt from Prof. Jacobson's response here:

• First, LOG skips over the first of my two main points, that Warren maintained an "office for the practice of law" and had a "systematic and continuous presence" practicing law in violation of Rule 5.5(b).  She had an office in Cambridge, she practiced law in it for 15 years continuously earning large fees in numerous cases, and she used it as her office address for her law practice in court filings.  There's nothing real complicated about it.
• LOG asserts that preparing legal briefs from an office in Massachusetts is not practicing law in Massachusetts if it involved federal law, but LOG cites zero authority for that.  You can't just make stuff up and call it a legal argument.  Not even on a blog.  In fact, as cited in my original post, preparing legal briefs clearly is within the definition of practicing law under Massachusetts case law.  See Section 3 of my prior post.  It's what lawyers do.
• The LOG claim that Rule 5.5(d) saves Warren, which LOG says is the most important point, is wrong.  The subsection in question, 5.5(d)(2) says "(d) A lawyer admitted in another United States jurisdiction, and not disbarred or suspended from practice in any jurisdiction, may provide legal services in this jurisdiction that: ... (2) are services that the lawyer is authorized to provide by federal law or other law of this jurisdiction." This does not apply to Warren because there is no claim that there was a federal law or other law which permitted her to practice in Massachusetts.  If a federal court somewhere granted her the right to appear in that court, it only would cover that court and would not usurp state Bar licensing requirements.  No one is claiming, for example, that Warren violated Supreme Court admission rules, but nothing in her Supreme Court admission gave her the right to maintain a law office or practice law in Massachusetts.  This is a distinction a lot of people commenting on Warren have confused.  Ed Whelan notes this distinction over at NRO.
• Continuing with Rule 5.5(d)(2), you can't have it both ways,  and say she was not practicing law in Massachusetts, but then saying there was a federal or other law (which you don't cite) which says she can practice in Massachusetts.
• LOG also makes a strawman argument about Warren not violating advertising rules.  I make no such claim.
• None of this legal analysis is particularly complicated.  It's made complicated only because of how much Warren defenders have to spin in order to claim that representing numerous corporate clients from an office in Massachusetts for 15 years earning hundreds of thousands of dollars is not practicing law in Massachusetts.

(added) Good to see John Hinderaker is on the case picking apart the baseless argument at LOG:

So the question is, what "federal law or other law of this jurisdiction" would allow Warren to practice law in Massachusetts, even though she doesn't have a Massachusetts law license? Neither she nor her supporters have suggested any such law that might apply.

Update: John Hinderaker of Powerline further debunks the critique of Prof. Jacobson's work.

Hat tip: Mark J. Fitzgibbons