The US-based rights group called on King Hamad bin Isa Al Khalifa to change Bahrain's judiciary's decision on the case of the detained medics, stressing that the "convictions were based in part on confessions obtained by torture and in proceedings that were fundamentally unfair."
“We are reluctant to call on the king to reverse a judicial decision, but time and again we have seen Bahraini courts uphold politically motivated charges against those who peacefully dissent," said Joe Stork, deputy Middle East director at Human Rights Watch in a statement.
"The courts have failed to uphold Bahrain's obligation to protect free expression and peaceful assembly,” the statement continued.
Bahrain's Court of Cassation, the country’s highest court last week rejected the appeals of all nine medics and upheld the prison sentences ranging between one month and five years.
The court rulings drew international condemnation to the US-allied Persian Gulf state with Amnesty International calling it a "dark day for justice."
The Bahraini revolution began in mid-February 2011, when the people, inspired by the popular revolutions that toppled the dictators of Tunisia and Egypt, started holding massive demonstrations.
Dozens of people have been killed in the crackdown, and the security forces have arrested hundreds, including doctors and nurses accused of treating injured revolutionaries.