At 4:45 a.m. on July 8 , a man wearing black and a mask broke into my apartment in Kyoto. He walked into my bedroom, attacked me and my partner with a chemical spray and escaped. Nothing was stolen. The Japanese police arrived quickly. The investigation is ongoing; the perpetrator has not been apprehended.

No official conclusion has been reached about who executed, much less orchestrated, the attack, but it matched a trend of harassment — and sometimes abduction and even killing — targeting anti-monarchist Thai dissidents overseas.

The 2014 military coup against the democratically elected government of Yingluck Shinawatra prompted hundreds of people to flee Thailand and go into exile, especially among supporters of Ms. Yingluck and her brother Thaksin, also a former prime minister who was deposed. Many backers of the Shinawatras, the so-called red shirts , went to neighboring countries seeking sanctuary, legally or not.

I am a political scientist and have long been critical of the Thai monarchy. Just days after the 2014 coup, I was summoned by the junta. I did not go. A warrant was issued for my arrest. My passport was revoked. I was already residing in Japan then, and I was forced to apply for refugee status there. My relatives in Bangkok were harassed by military officers. I believe that the attack against me this summer, in my home in Japan, was a warning for my continuing to hold , and express , my positions.