Government could have assigned the data collection tasks to virtuous law enforcement or enlisted the integrity of private enterprise but did not do so, the cost would have been enormous. Instead, government imposed a continuing duty of self-reporting on the untrustworthy ex-felon to supply critical public safety data at his own expense. That is clearly exploitation and was no doubt intentional.
Government utilizes registrants as an implement to acquire and maintain data. Registrants are implented and employeed and hence employees as defined by 5 USC 8101(1)(B):
"an individual rendering personal service to the United States similar to the service of a civil officer or employee of the United States, without pay or for nominal pay, when a statute authorizes the acceptance or use of the service, or authorizes payment of travel or other expenses of the individual"
Because it would require at least 3 agents salaried at $70,000 to track 1 individual around a  hour clock and report back the required public safety data, we estimate the value of that data service to exceed $200,000 per year, per individual, as the approximate cost to government of acquiring the required public safety data at its own expense.
Private businesses scrape the forcibly acquired data from government websites and redistribute it for money generating purposes. E.g. Homefacts.com. Community members no longer must travel to the courthouse for criminal history data or fund background investigations. Law enforcement uses the data for its internal purposes. The subject civil data service clearly possesses significant economic value regardless of the growing numbers who disavow the effectiveness of registration laws at preventing crime.
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