The "No True Scotsman" fallacy refers to excluding members from a group by means of moving the goalposts - which is to say, continually changing the minimum requirements of group membership in order to exclude someone.

However, this does not mean that a kangaroo is a shark, even if the kangaroo earnestly believes it is.

The Tea Party grew out of frustration with business as usual in Washington, and frustration with entrenched Republican politicians in particular. Lamar Smith had been in Congress for 20 years when the Tea Party began.

The Tea Party originated with supporters of Ron Paul. One of Ron Paul's signature causes has been opposition to the Drug War. Lamar Smith has a history as a Drug Warrior, and in 2009 shot down a bill that was co-sponsored by Ron Paul and Barney Frank, which sought to end prohibition of Marijuana.

Furthermore, the Tea Party Caucus is not popular with the Tea Party, many of whom consider it an attempt by Republicans to hijack the movement ⚠️ ↗.

At best, Lamar Smith is a hanger-on. He certainly does not represent the average tea partier who started the party to get rid of politicians like Lamar Smith.