China is risking another legal defeat if it pushes through with arrests of Filipino fishermen in the West Philippine Sea, retired Supreme Court Associate Justice Antonio Carpio said Monday.

A South China Morning Post article earlier said Beijing has fleshed out the Chinese Coast Guard’s powers to detain foreigners “suspected of illegally crossing borders.”

It said suspects “can be held for up to 60 days without trial.”

Commodore Jay Tarriela, Philippine Coast Guard spokesperson for the West Philippine Sea (WPS), earlier described the new regulations as an “empty threat” designed to scare off civil society groups from mounting more aid missions into the territory. 

Philippines to snub China's arrest threat vs 'trespassers'

Carpio said the 2016 arbitration ruling invalidated China’s nine-dash line claiming parts of the South China Sea, including the West Philippine Sea. This means Philippine authorities can immediate file a case against China if Beijing arrests Filipino fishermen who are fishing in the West Philippine Sea.

“’Yung pag aresto at kinulong ‘yung fishermen, pwede tayong mag file ng case. Punta ulit tayo sa UNCLOS tribunal dahil klaro naman na labag sa UNCLOS. Bawal na mag aresto sila ng fishermen sa ating exclusive economic zone,” he said in a TeleRadyo Serbisyo interview.

Carpio said any court case filed against China for violating the 2016 arbitration ruling would be a sure win for the Philippines despite Beijing’s insistence that it does not recognize the ruling.  He doubted, however, that Beijing would even show up for the trial, knowing that they will lose. 

“Magsasampa ulit tayo ng kaso at siguardong matatalo siła diyan,” he said.

He pointed out that other countries including the United States have used the arbitration ruling to conduct freedom of navigation trips in the area.

“That is the strongest enforcement of the arbitral award, telling China ‘this is not yours,’” he noted.