In a statement, Estrada said the detention of 1st Lt. Artemio Raymundo at the Philippine Marine Corps in Fort Bonifacio since Sept. 26 is a "blatant abuse" of human rights.
"I denounce in the strongest possible terms the ill treatment accorded to 1st Lt. Raymundo," he said.
"He has committed no crime against any individual, private or public institution, or any government office and as such there is no basis for his detention or a court -martial.
"It is grossly unfair to treat this young officer like a criminal when he, together with all those who have not stood in the way of more people viewing this documentary, are merely exercising their constitutional rights.
"If this kind of crackdown goes on, there is no longer any doubt that we have all become hostages to a government that pretends to uphold democracy but is actually practicing the tenets of undeclared martial rule."
Estrada said the "unabated politics" prevailing in the AFP was polarizing the ranks.
"It is contributing to polarization in the ranks, with some officers towing the palace line for the promise of rewards and others doing as their conscience dictates in support of the rule of law," he said.
Estrada said the AFP brass is depriving Raymundo of his right to confer with a lawyer, based on reports reaching him.
"Every citizen has the right to confer with his legal counsel, and deprivation of such indicates we are operating under a police state," he said.
"I call the attention of the distinguished members of the Integrated Bar of the Philippines to look into this situation, and assist Lt. Raymundo in his fight to exercise his rights."
However, the Armed Forces denied yesterday that Raymundo would be charged before a court-martial for allegedly distributing copies of Estradas film.
Lt. Col. Bartolome Bacarro, AFP public information chief, said the military brass has not banned the distribution of "Ang Mabuhay Para sa Masa."
"Wala kaming directive na bawal ang possession (of the CD)," he said. "But definitely we all agree na may political color iyon."
Bacarro said that it was probably "prohibited" by Marine Maj. Danilo Luna, Field Artillery Battalion commander, due to his "inherent job of insulating his troops from partisan politics."
Bacarro, said Raymundo, who commands 16th Marine Company, was not being charged for distribution of copies of the film, but for disobeying his superiors order.
"When he was asked not to distribute, nagwala siya at sinagot sagot ang commander niya (He answered back his commander)," he said.
Raymundo is facing violations of Articles 64 (disrespect to superior officers) and Article 65 (insubordination).
Lt. Col. Ariel Caculitan, Marine spokesman, said Raymundo has been confined to barracks since last month.
"An investigation was conducted at the level of the battalion," he said.
"The recommendation was that he be made to face the general court martial for investigation. The results of the investigation were forwarded to the Marine Judge Advocate Generals Office (JAGO)."
Marines who received a copy of Estradas film reported Raymundo to their superiors, he added.
Produced by PublikAsia, "Ang Mabuhay Para sa Masa," which traces Estradas life as an actor and a politician, was given an X-rating by the Movie and Television Review and Classification Board.
The Manila City government also denied Estradas film a permit for a public exhibition at the Plaza Miranda, a designated freedom park, Quiapo, Manila.
At present, the film is being reviewed by an ad hoc committee created by Malacañang, which will decide with finality whether it can be shown in public. Mike Frialde, James Mananghaya