The rent is too high. After historic surge, is relief on the way?

The landlord’s letter sat on her dining room table for three months. The rent on her two-bedroom Boston apartment was going up $300 a month. Then, Betty Lewis made her decision: She wouldn’t pay the increase.

So every month for the past four years, she has paid her 2018 monthly rent of $1,800 a month, ignoring subsequent increases and monthly fines for failure to pay.

“I was frightened. I was angry,” says Ms. Lewis, who credits a tenant-rights group, City Life/Vida Urbana, for giving her the courage to act. “It just gave...