I think you can be sued in the civil court for anything if someone has the time and money and can convince a lawyer to take up a case against you. For copyright infringment, you can also be criminally prosecuted in some cases.
Here’s the summary for the wikipedia article you mentioned in your comment:
Criminal copyright laws prohibit the unacknowledged use of another's intellectual property for the purpose of financial gain. Violation of these laws can lead to fines and jail time. Criminal copyright laws have been a part of U.S. laws since 1897, which added a misdemeanor penalty for unlawful performances if "willful and for profit". Criminal penalties were greatly expanded in the latter half of the twentieth century, and those found guilty of criminal copyright infringement may now be imprisoned for decades and fined hundreds of thousands of dollars. Criminal penalties, in general, require that the offender knew that he or she was committing a crime, while civil copyright infringement is a strict liability offense, and offenders can be "innocent" (of intent to infringe), as well as an "ordinary" infringer or a "willful" infringer.
Could be that your client, like mine, doesn’t support this particular flavor of markdown, or the markdown could just be wrong. I’m honestly not sure which.
