Human Rights Watch and the Moroccan Association for Human Rights said in a joint statement on Wednesday those arrested over the past five months include students, artists, citizen journalists and social media commentators and are facing such charges as showing a "lack of due respect for the king", "defaming state institutions" and "offending public officials".
According to the statement, some of those detained "have targeted the wealth and lifestyle of King Mohammed VI, contrasting it with what they perceive as the state's failure to guarantee basic rights and economic opportunities for young Moroccans".
"Others encouraged people to participate in protests against socio-economic injustice," the rights groups added, Presstv reported.
The rights groups said prosecutions were being conducted under the criminal law rather than the four-year-old Press and Publications Law so the courts can hand down jail terms where they saw fit.
Ahmed Benchemsi, HRW’s Middle East and North Africa communications director, noted that a growing number of Moroccans “are taking to social media to express bold political opinions, including about the king, as is their right."
He added that the authorities have stepped in to frantically try to reinstate the red lines as self-censorship erodes.
Asked about the prosecutions last month, Hassan Abyaba, a spokesman for the government, insisted "the human rights situation in Morocco is not regressing", adding there was a distinction between "those who express themselves freely and those who commit crimes punishable by law".
The US-based HRW said that in partnership with the Moroccan Association for Human Rights, it was launching a list of free speech cases that it would keep regularly updated.
The operators of popular YouTube channels "Moul Kaskita" and "We Love You, Morocco", who got four- and three-year jail term, respectively, for showing disrespect to the king, are among those inscribed on the list.
Another name on the list is Omar Radi, a journalist who faces up to a year in prison for slamming judge Lahcen Tolfi in a tweet in April 2019 after he upheld sentences of up to 20 years in prison against leaders of a protest movement that hit the country in 2016 and 2017.
Moroccan Association for Human Rights secretary general Youssef Raissouni said "Expressing nonviolent opinions should never be a crime sanctioned by prison terms."