This is a classic approach used in Russia and other countries against anti-ruling-party organizations, but I had (probably naively) expected USA to be better than this.
IRS does. And if they stop investigating right-wing organizations selectively (while still investigating other applications) because it will be perceived as unfair, then they will be doing the wrong thing.
Harassing, no; but it's reasonable to presume that members of groups which agitate for marijuana legalization are more likely to be growing, selling, and/or using marijuana illegally, and thus to have a higher index of suspicion if presented with evidence which might indicate that such illegal activities are taking place.
To take an extreme case: If I travel around the US and tell everybody I encounter that I think the White House should be blown up, I think it would be entirely reasonable for the Secret Service to investigate. I might make such proclamations out of abstract personal convictions, or I might make them because I'm the sort of crazy person who would actually try to blow up the White House; the whole point of investigation is to determine which.
As a result, US jurisprudence has grown to recognize the potential for government acts to have "chilling effects" on individual rights, even with no evidence of overt bias. Under this theory, certain civil rights (speech, religion, voting, due process) are so terrifically important that government must err on the side of caution, rather than risk discouraging their exercise.
Of course, as with any civil rights issue, we do consider the severity of circumstances in each case. Unfettered free speech swings a lot of weight, but there are always exceptions. Preventing violent terrorist acts (as in your last example) might justify allowing some chilling effects on speech.
However, the courts have vigorously protected speech advocating NON-violent criminal acts (sit ins, protests, draft-card burning) and changes to current laws (drug prohibition). This category seems to cover both your earlier example (marijuana reform), as well as the original situation (tax reform).
And FWIW, kids: This little back-and-forth is a great example of why arguments by analogy don't work.
The acting Commissioner of the IRS is Steven T. Miller and was appointed by the Obama Admin (as of Nov 10th 2012).
http://www.allgov.com/officials/shulman-douglas?officialid=2...
2) No one has (yet) suggested that this went all the way up to the Commissioner level.
Nice spin attempt, though.
This sounds an awful lot like a bureaucratic directive ("there's an awful lot of alleged tea party groups raising a lot of dough, keep an eye out") being reinterpreted through the conspiracy lens