I've noted previously that the only way photo ID can be constitutionally required of voters is to make it available for free. Otherwise, it is a poll tax.
So, how much would that cost?
Colorado issued 110,987 state IDs (other than driver's licenses) in 2005 (see page 39). These cost $7.60 for those under age 60, and are free for those over 60. We don't know the exact breakdown by age, so we can't know for certain what revenue is generated. Also, processing state ID would be more expensive, because additional scrutiny of IDs would be required, and more people would need to get them.
It could easily cost $1,000,000. Suppose that the statistics previously cited in that post are also correct, and there are perhaps 20 non-citzen voters each year in Colorado.
Do we really want to spend $50,000 per non-citizen voter, and disqualify all those valid voters, in order to achieve this objective? And, there is no guarantee that all of the 20 non-citizen voters, dispersed across the state, would be stopped from voting, if they are truly determined, as fraudulent documents could still be used to get fake state IDs for other purposes, and no one is proposing comprehensive auditing of every single application.
Is this really the best use of public money? If we are going to spend money to make voter rolls accurate, there are far more cost effective ways to do it, like coordinating Department of Corrections and voter registration official's databases. It might cost a similar amount, but would probably impact 100 times as many unauthorized voters, and hence cost perhaps only $500 per improper voter excluded. Or, we could simply allow parolees to vote, by changing the law, and spend that money on a more urgent issue facing Colorado, like vaccinations in a state with one of the lowest vaccination rate in the country. What is more important? Sick and dead kids, or keeping adults who live in Colorado from voting when there is very little improper voter fraud as it is? $1,000,000 will vaccinate a large share of all children in Colorado who don't get vaccinations now.
Is this apples and oranges? Sure it is. This is what we elect legislators to do, compare apples and oranges and make fuzzy judgment calls this this one. The case for this particular expensive and bureaucratic approach to the alleged problem is not a strong one.
Also, there are easier ways to deal with unauthorized voters that would cost far less. For example, the name and date of birth of every person that "bounces" from an employer's employment eligibility check, every person who shows up to court for jury duty and uses lack of citizenship as an excuse, every person denied state benefits on the basis of citizenship, every foreign student in the state, and everyone classified as a non-citizen for local jail officials, could automatically be forwarded to the Secretary of State's office. The Secretary of State could in turn forward the comprehensive list to each of the county clerks or election commissions, as the case might be, on a regular basis, for administrative comparison to voter registration records. This could be done largely using existing resources, plus a simple database program. This would systematically clean up the voter registration rolls of high probability problem cases, while not burdening the general public with new impediments to voting.
When something doesn't happen very often, management by exception is the way to go. Overarching requirements for every person only make sense when cheating is common place. This approach greatly reduces "false positives" of legitimate voters disqualified administratively, while still making a real impact on the number of improper voters removed from the voter rolls.
Universal photo ID requirements for voters simply do not make sense and literally disenfranchise against the weakest and least affluent in society.