I have heard from Andy Taylor, the attorney that trained me as a poll watcher. I followed my training in the challenge I attempted Thursday. Here is what Mr. Taylor had to say on the matter. . .
You've put your finger on an area of controversy. I am telling everyone to use the challenge procedure if a voter gets illegal assistance. For example, a precinct judge goes up to a voter not entitled to assistance (not blind or illiterate) and says, "Here's how to vote for Tony Sanchez..." That ballot CANNOT be counted. The problem with the code is that there is no specified procedure for documenting the challenge. So I train everyone to go ahead and use the preprinted SOS form that challenges a voter's eligibility to vote. Now, strictly speaking, that form is directed to a voter who for some reason can't vote (like not registered). And, in the illegal assistance hypothetical, the voter may be legally entitled to vote, but the illegal assistance renders that voter's ballot illegal. So you can make the argument that the challenge form I gave you isn't the right form or the right format to raise this objection. The problem with that, though, is the challenge procedure is the only method to get a ballot stub for a particular vote, which ties the potentially illegal vote with a particular voter. So, in the absence of a specific form by SOS for registering an objection to unlawful assistance, it seems to me that it is easier to simply use the document you have.
I did tell you that the judge will only have a few of these, so that's why you should bring 50 with you. Also, you should use these if people vote past 7pm, irrespective of whether a court says the poll should remain open, for the simple reason that this is the only way to segregate the votes with ballot stubs.
So, in summary, stick to your guns. Thanks and good luck.
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Man, vindication is a good feeling. Okay, fellow poll watchers across Texas - DO challenge unlawful assistance.
Antivenom, Petroni or any other election judge - we need a PDF version of the challenge form for poll watchers to download. I can place it on my server if needed.