Colorado has about 3.8 million registered voters, but only 3.3 million of them are considered "active."

A conservative group with a history of making false and misleading claims is threatening to sue Colorado and Jefferson County if they don’t speed up the process of removing inactive voters from the county's voter registration list. State and local officials say the group is misreading federal law — and got its math wrong, to boot.

In a letter sent to Jefferson County Clerk and Recorder George Stern and Colorado Secretary of State Jena Griswold in December, an attorney with the conservative nonprofit Judicial Watch alleged that Jefferson County is violating federal law by not making a “reasonable effort” to purge ineligible voters from its rolls.

“If you do not contact us about correcting or otherwise resolving the above-identified problems within 90 days, a federal lawsuit seeking declaratory and injunctive relief against both of you in your official capacities may be necessary,” said the letter from Judicial Watch’s Robert Popper.

In a statement, Stern said that the group is “using questionable math to imply that we have more registered voters than are eligible or that we are not complying with federal law as it relates to the removal of inactive voters. Both contentions are patently false.”

Judd Choate, elections director for the secretary of state’s office, agreed, noting that the letter was “not atypical behavior” for Judicial Watch and that its past allegations have proven baseless.

“This is Judicial Watch’s failure to understand federal law,” Choate says. “Because you can’t just remove somebody because you don’t like their voter file. You have to remove them under federal law.”

Judicial Watch’s letter alleges that Colorado is in violation of a section of the National Voter Registration Act that requires states to “conduct a general program that makes a reasonable effort to remove the names of ineligible voters” from their rolls. But officials say that the group is ignoring another section of the same law that spells out how registrations can be canceled.

“We as a county are prohibited from removing inactive voters from the registration rolls unless they meet specific criteria, including first becoming inactive and then failing to respond to mail and vote in two federal elections,” Stern said.

In Colorado, voters are designated as inactive when mail sent to their registered address is returned as undeliverable. There are more than 500,000 inactive voters statewide; they remain registered and eligible to vote if they visit a polling center, but they don't get sent a mail-in ballot like the state's 3.4 million active voters do.

The Judicial Watch letter is part of a larger effort aimed at speeding up voter purges in multiple states, including crucial 2020 battlegrounds like Pennsylvania, North Carolina and Virginia. In recent years, Judicial Watch lawsuits have successfully led to the mass removal of voter registrations in Ohio, Indiana and Kentucky, and have been widely denounced by civil-rights groups as a voter-suppression tactic.

In a 2018 report, the Brennan Center for Justice called voter purges an “often-flawed process” that can “prevent eligible people from casting a ballot that counts.” Across the country, more than 16 million voters had their registrations canceled between 2014 and 2016, and federal judges, including the U.S. Supreme Court, have repeatedly upheld aggressive voter-purge schemes in GOP-controlled states in recent years.

Republican politicians, including President Donald Trump, frequently make baseless allegations of widespread voter fraud, using their claims as pretext to enact strict new voting laws that civil-rights groups argue have the effect of disenfranchising eligible voters. Studies have consistently shown that voter fraud is extremely rare, finding a few dozen isolated cases of voter impersonation out of more than a billion votes cast in U.S. elections since 2000.

Founded in 1994, Judicial Watch rose to prominence as an aggressive antagonist to President Bill Clinton’s administration, and its controversial efforts included promoting the conspiracy theory that Clinton had murdered former aide Vince Foster. Over the years, the group has called climate change “fraud science” and repeatedly spread hoaxes and misinformation: In 2015, for example, its website quoted unnamed “Mexican sources” to claim that the terrorist group ISIS had set up camp in Mexico, just eight miles across the border from El Paso. (It hadn’t.)

In its letter to Jefferson County, Judicial Watch alleges that the county claims that “the number of voter registrations exceeds the number of citizens in the County who are old enough to register to vote.”

U.S. Census Bureau data, however, indicates that this claim is false: An estimated 580,233 people live in Jefferson County, according to 2019 data, 19.7 percent of whom are under eighteen. Voter registration data from the secretary of state’s office shows that as of last month, the county has 386,177 active registrations and 45,779 inactive registrations — less than the county’s Census-estimated voting-age population, even when inactive registrations are included.

Judicial Watch did not respond to Westword’s questions about the data or methodology it used to make its claim. Jefferson County officials also disputed the group's assertion that the county is only removing "about 6,100" registrations per year, saying that more than 20,000 voters were removed from the rolls following the last federal election.