Guerillero is one of the members of Wikipedia's Arbitration Committee who banned our editor Coat of Many Colours following a complaint by the Wikipedia editor Hafspajen that Coat was hacking Hafspajen's computer. Hafspajen later claimed that it was Wikipedia itself that was hacking her computer. The issue was investigated by Wikipedia and no evidence was found to suggest that Hafspajen's account had been compromised. Hafspajen nevertheless continued to maintain that Wikipedia was hacking her computer and ceased editing at the beginning of the year (2016).
Guerillero doesn't self-identify on his User page. However his Commons account is more forthcoming and one is quickly led to a Commons image that identifies him. It's easy to locate his personal website, where he identifies himself in the following terms:
I am a Wikipedian, cartographer, public policy junkie, and code monkey. I recently finished my degree at Washington College in Anthropology and Philosophy. My favorite thing to do is to make maps, charts, and websites that help people understand little-known parts of the world around them. I currently work for my alma mater maintaining and building enterprise software.
On Wikipedia, I serve as an administrator and an Arbitrator. My major contributions to the encyclopedia include articles about punk rock, protesting nuns, and folk songs. My username isGuerillero.
If you would like me to consult for your company or non-profit about Wikipedia, online communities, or GIS contact me, and I will see what I can do.
Edit stats conducted early-May 2016 show that Guerillero has made some 18,000 edits over a seven year period, averaging some 7.5 edits a day. Only 26% of these are in article space.
Guerillero seems to be a fairly uncontroversial member of Arbcom. We did find this thread at Wikipediocracy about his role in the so-called Gamergate controversy, of which we choose to know nothing (or everything as the case may be) and consequently recuse ourselves from comment.