Motahari’s remarks came during a speech he delivered in Tehran at the 15th general conference of Iran’s reform-leaning Democracy Party.
In his speech, Motahari said that the jailing of prominent cleric Ahmad Montazeri, sanctions imposed on opposition leaders Mir-Hossein Mousavi and Mehdi Karroubi, and a media ban on former President Mohammad Khatami “are all inconsistent with Iran’s constitution”.
“The Iranian people are unhappy with these unconstitutional practices -- including house arrests, media bans and detentions -- and demand an end to such violations," he asserted.
“The people have been very critical of the state since the events that followed Iran’s 2009 presidential elections,” Motahari added. “Since then, we have seen numerous constitutional violations.
On Wednesday, Montazeri was sentenced to six years in jail for releasing an audio recording of his father, Ayatollah Montazeri, criticizing the execution of members of the opposition Mojahedin-e-Khalq organization in 1988.
Mousavi and Karroubi, meanwhile, have remained under house arrest since 2011 -- without ever having faced trial -- due to their objection to Iran’s 2009 presidential poll results.
And in early 2015, prosecutors in Tehran banned the publication of photographs or video of Khatami in the media.
One of the campaign promises of President Hassan Rouhani, who assumed office in mid-2013, was to abolish the practice of house arrest.