The brothers received their time-determined sentences in the spring, from lifetime without the possibility of pardon to 50 years to lifetime, after having sat for more than 30 years in prison.
As the judgment was mitigated, they had the opportunity to apply for conditional release. The younger brother will, however, have to wait at least three years before he can apply again.
The ruling for Lyle Menendez is expected on Friday morning, local time.
The brothers were sentenced in 1990 to life imprisonment for the murder of their parents.
The case has been made topical with the Netflix series "Monster: The Story of Lyle and Erik Menendez" and in the documentary "The Menendez brothers" from last year.
