> everything we did was in pairs of republicans and democrats

Question: What constitutes a Democrat or a Republican? Is registering as one enough? What guarantee is there people aren't lying about the parties they identify with?

I don't know about the system in that particular county, but the system in most democracies is that any candidate has the right to appoint a representative to be present. In practice this means that the parties run down their lists of volunteers; depending on how many volunteers they have in a particular area it might be very easy for someone to get appointed as such. (In the last Canadian election, I turned up on election day to volunteer for a friend who was a candidate for a major party, and six hours later I was an Official Candidate Representative scrutinizing the vote counting.)

Good to know -- thanks for the anecdote!

> What guarantee is there people aren't lying about the parties they identify with?

You, when you volunteer to work at the polls or as a party observer, thereby increasing the redundancy of the checks.

that's a risk you have to take, at some point. you eventually have to trust that someone isn't lying, somewhere along the chain.

what else could be done to further vet volunteers? you can't interrogate people or drug them with serums for the truth, so I think it's safe to assume registering is enough.

so, to answer your question, I doubt there is any "guarantee" other than the fact that these are volunteers and you'd have to be a real idiot to falsely register to ensure you can tilt the scales...of bipartisan pairs of Arapahoe County poll volunteers.

> that's a risk you have to take

Well, obviously. But the risk can be high or low, right? You could either let any random voter you don't know walk in and become a volunteer after filling out a form, or you could let maybe ~50 people that the party's head/nominee personally trust pick a set of volunteers nationally based on e.g. personal knowledge or some concrete evidences of their past contributions and allegiance to the party. Or something else; there are lots of possibilities here. So I'm asking what the criteria are so I can understand how likely it is for something to go wrong here... I obviously understand nothing 100% bulletproof, so there's no need to point that out.

Maybe it's just me, but I think I would be more comfortable pulling 50 random people off the street to count votes than I would be with 50 volunteers appointed by the candidates, who have a much bigger incentive to violate the integrity of the vote (if needed).

let's take this a step further: two republicans, one falsely registered as a democrat, have been paired off at the polling station in Araphaoe County. the lie was bought, the fraud complete. now what?

The "real" Republican sees his "Democrat" counterpart attempt to tamper with the machine and saying "trust me, I'm doing it for the Republicans". They yell for assistance.

that's about what I figured. I can't see a clear benefit or advantage to having one rogue false registrant make a single pair weighted towards one party or the other.

> let's take this a step further: two republicans, one falsely registered as a democrat, now have been paired off at the polling station in Araphaoe County. the lie was bought, the fraud complete. now what?

I don't know, but you seem to be completely ignoring my point. I'm trying to figure out the probability of this happening. I'm NOT trying to figure out what to do after this happens.

Did third parties get representation?

Not sure about elsewhere, but in Canada, any candidate on the ballot is usually allowed to appoint up to two agents or scrutineers per ballot box, usually to spell each other off (it can be a very long day)