Nairobi, May 5 -- In 2016, two years after Kenya ushered in the Marriage Act, Siriri* was a happy police officer. He married his sweetheart in a church wedding in Kakamega County. But just four months later, before they had fully enjoyed the sweetness of their honeymoon together, he was transferred to Nairobi, while his wife chose to remain in their rural home.

She was tending their farm, and because he had left during the rainy season, he continued to send money home for her upkeep and to support maize farming. Then, in the third month of living apart, he called to check in on her. She informed him that she had travelled to her parents' home to take a break from the demanding farm work.

That was the last he heard of her. "She never ret...