This much is clear: Kano State authorities in northern Nigeria accused the Sufi Muslim singer Yahaya Sharif-Aminu of circulating social-media messages containing lyrics they said attacked the Prophet Muhammad.

 What did the song say? It's impossible to find direct quotations, although his accusers say he sang praises for his Sufi faith and, thus, spread false teachings about Islam.

 Did Sharif-Aminu actually send those WhatsApp messages? Again, it's hard to separate facts from rumors backed by mob attacks.

But this much is clear: Sharif-Aminu was found guilty of blasphemy in 2020 by a regional sharia court and sentenced to death by hanging. He remains imprisoned, while human-rights activists around the world -- including the European Union parliament -- keep urging his release and the end of blasphemy laws.

"You're not sure, in many of these cases, what the person is actually accused of doing or saying because key people are afraid to discuss the details," said scholar Paul Marshall, who teaches at Baylor University in Waco, Texas, and lectures around the world. He is the coauthor of "Silenced: How Apostasy and Blasphemy Codes Are Choking Freedom Worldwide," with Nina Shea of the Center for Religious Freedom at the Hudson Institute in Washington, D.C.

The result is a deadly puzzle. Anyone who shares facts about blasphemy accusations may then be accused of spreading blasphemy. Depending on the time and location, any public opposition to blasphemy laws may be considered an act of blasphemy.

Meanwhile, the definitions of "apostasy" and "blasphemy" keep evolving when used in cultures as different as Pakistan, Iran, Iraq, Syria, Egypt, India and parts of Africa controlled by Islamic State leaders and its sympathizers, Marshall explained.

Members of religious minorities -- especially Ahmadi Muslims, Sufis, Bah'ais and converts to Christianity -- may be accused of fomenting "sectarian strife," spreading "misinformation," "insulting a heavenly religion" or threatening "national security." In regions controlled by Sunni Islam, rival Shia Muslims may face similar accusations, with that equation being reversed in lands, such as Iran, controlled by Shia clerics.

"If someone is accused of teaching a false version of Islam, that can be considered blasphemy, even if people do not use the word 'blasphemy' in the charges," noted Marshall, reached by telephone. "The words may vary, but not the intent in these cultures."

The Sharif-Aminu case is part of another trend, with accusations about alleged blasphemous acts and statements circulating instantaneously across the World Wide Web, often in smartphone videos, photos and audio soundbites that may or may not have been altered to twist the contents.

"People who are hackable may be getting framed," said Marshall. "That's where the offenses and accusations are picking up."

In bitterly divided Nigeria, sharia courts in the majority-Muslim north have issued rulings clashing with the nation's laws, and its constitutional guarantee of religious freedom. These tensions were noted in an urgent April 20 resolution by the European Parliament, which attacked blasphemy laws and called for Sharif-Aminu's release.

Also, in May 25 remarks in the House of Commons, British Prime Minister Rishi Sunak's special envoy for religious freedom issued a direct appeal to Nigeria's outgoing president, Muhammadu Buhari. Fiona Bruce urged him to "exercise clemency by granting a pardon to the young Sufi singer, Yahaya Sharif-Aminu" since his case is on appeal. "He was accused of blasphemy because a song he wrote was circulated -- as I understand it, by someone else -- on social media," she noted.

At the time of the original accusations, mobs "completely destroyed the family home and everyone ran for their lives," said Nigerian lawyer Kola Alapinni, who is working with ADF International on this case. The original legal proceedings were skewed by the fact that no lawyers stepped forward to defend Sharif-Aminu, since "they were scared for their lives."

While singer's original death sentence was "quashed," he said, this sent the case back for retrial in the sharia court -- which will almost certainly reaffirm the death sentence.

"You can think of all sorts of trauma going on in his head. … The whole family is devastated," said Alapinni, in a video statement.

"Nigeria is a very unique country. We are multicultural, we are multidimensional, we are a multireligious country, and we shouldn't be … bringing in laws that criminalize religion. It has no place in a country of 218 million people."