I would add that for e-petitions, when someone attempts to sign, they enter an email address. There's an email that's sent by the system to that address to validate that the address actually exists, and the person has to click on the link sent to that address before their signature will be counted. For an e-petition, there's a validation that the address exists.
For paper petitions, we don't go and see that Jeremy LeBlanc lives at whatever address was given. We don't verify to that degree. We just verify that the address format is accepted, the signature seems legitimate and doesn't look like it's in the same handwriting as all the other signatures on the page, and those sorts of things.