The Monitor of McAllen reports Arturo Almaguer appeared in a Weslaco, Texas, courtroom Friday.
The 43-year-old is charged with one count of capital murder, one count of murder and one count of burglary. He is being held on a $1 million bond.
Jail records did not list an attorney for Almaguer.
Police say Almaguer gunned down 70-year-old Evan and 65-year-old Wilda Squire in their seasonal trailer home on Nov. 13, 1988, in Weslaco.
Authorities say DNA evidence collected after Almaguer was arrested in December in Grand Rapids, Mich., on separate charges implicated him in the couple's slaying.
The Squires were from Minnedosa, Manitoba, about 120 miles west-northwest of Winnipeg.