China has sentenced a restaurant owner to 15 days in prison for allegedly hanging a Chinese flag upside down in his restaurant and using it as a curtain, an act police claim caused “an adverse effect in society.”

China recently passed a law mandating a 15-day jail sentence for anyone disrespecting the national anthem in any way, including playing the anthem in unauthorized settings. The law reflects existing regulation on the flag.

China’s state-run Global Times newspaper reports that restaurant patrons took photos of the man’s restaurant and posted them on social media. The photos began to trend due to their popularity, allegedly causing “an adverse influence in society.” The man has been identified only by his last name, Ma.

The Global Times says Ma will be in prison for “15 years,” but translations of the Mandarin-language report on the incident states that he will be in prison for only 15 days, as the new law requires.

Police asserted that an “investigation” found that Ma had bought the flag, and another copy, to use in celebration of an unspecified “local event,” but had only displayed one of the flags outside. The South China Morning Post identified the event as a cycling race, citing other local media.

The other he kept inside the restaurant. The popularity of his Chinese flag curtain triggered “heated discussions” online, the Global Times asserted, which was unacceptable to police.

“The national flag is a country’s symbol and represents a country’s sovereignty and dignity, and intentionally desecrating it insults the country’s dignity and damages the people’s patriotic passion,” police reportedly said in a statement.

The case is the first of its kind since China passed a law in September mandating 15-day sentences for simple cases of disrespecting the “March of the Volunteers,” the national anthem. The law took effect in October. Chinese officials insisted the law was necessary to “promote patriotism and nurture socialist core values.”

Use of the national anthem is now limited to “authorized” locations, which do not include funerals or “inappropriate locations.” It is illegal not to sing the anthem when it is playing. Reuters noted at the time that similar offenses to the flag have resulted in similar sentencing for decades. The South China Morning Post notes that new amendments to the law specifically ban burning, mutilating, or trampling the flag as well as overt gestures of disrespect.

Lawmakers also debated banning placing one’s hand on one’s heart during the playing of the national anthem, arguing that it was too “American” a gesture and clashes with Chinese patriotism.

The law has been especially controversial in breakaway regions and autonomous areas like Hong Kong, where many do not feel Chinese and resent Beijing’s attempts to enforce Chinese law over the free region.

Among the most controversial cases has been that of Cheng Chung-tai, a Hong Kong legislator arrested for turning Chinese flags flown within the region’s Legislative Council upside down as a form of protest. Cheng’s legal team is arguing that he did not mutilate or harm the flags in any way, as so cannot be tried for “desecration.” He argued that other opposition lawmakers had removed some flags, as well, which would require the Chinese government to prosecute them, as well.

“At issue was how ‘defile’ is interpreted under the city’s laws, which do not offer specific definitions, except to list five examples that include burning, mutilating, scrawling on, and trampling the flag,” the South China Morning Post argues.

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