Amy Dillard suspects carbon monoxide is leaking from her stove. Electrical problems left Verena Dunn with hundreds of dollars’ worth of spoiled food. Richard Langley’s apartment flooded every time it rained.

Until last spring, when the Housing Conditions Calendar opened as a new forum for tenant complaints in District of Columbia Superior Court, Dillard, Dunn, Langley and the more than 300,000 other renters in Washington had few legal remedies if landlords failed to make repairs, according to tenant advocates.