MINNEAPOLIS (AP/WCCO) -- A Little Falls man serving two life sentences for killing two teenage burglars is appealing his conviction.

Byron Smith has filed a notice with the Eighth U.S. Circuit Court of Appeals which argues the courtroom denied him his constitutional right to a public trial by closing the courtroom off to spectators and the press for a short period before opening statements.

The notice is the latest in a number of legal filings by Smith to have his convictions overturned. The Minnesota Supreme Court has ruled the courtroom closure was an administrative proceeding so the right to a public trial law does not apply.

Smith fatally shot 17-year-old Nicholas Brady and 18-year-old Haile Kifer on Thanksgiving of 2012 as they broke into his home. Smith claimed self-defense.

The combination of audio and photos gave the jurors what they needed to conclude this was not a homeowner surprised by intruders, but a man who planned for a violent confrontation.

(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)