9NEWS (Denver): With six days until Election Day, a federal district court will decide whether to invalidate a Colorado state law that bans voters from showing their completed ballots to other people.

The law predates the internet, but has become known as a ban on “ballot selfie” because the state interprets it to mean that it’s illegal to post a photo of a filled-out ballot online.

Courts have struck down similar laws in other states and federal judge Christine Arguello seemed deeply skeptical that Colorado’s law would pass constitutional muster.

Lawyers for the state argued that Colorado believes its law is constitutional.

“Then you have a problem,” Judge Arguello quipped in reply.

Arguments from lawyers for the state and the Denver District Attorney’s office seemed to do more to convince the judge that the law ought to be blocked.

The attorneys defending the 125-year-old law told the court they would not prosecute anyone for violating it unless it a suspect also violated other election laws, which the judge interpreted as “an indication that you believe there is a problem with this law.”

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