Asked if she felt 100 percent certain the right man had been convicted of the crime, Susan Levy said on the CBS "Early Show" Monday that, "To be honest, I always have that 5 percent of not being sure."
Friday, Guandique was sentenced to 60 years in prison.
He was convicted in November of first-degree murder in Levy's 2001 disappearance and death. The guilty sentence came despite no witness testimony and no DNA evidence linking him to the crime.
During Friday's sentencing hearing, Susan Levy told Guandique he was "lower than a cockroach" and called him a "hideous creature."