D.C. Code § 42-3505.55: Housing provider's consent before subletting.

A housing provider may, in its sole and absolute discretion, prohibit subletting of the premise or assigning a lease, either in part or in full; provided, that the prohibition is included in the lease. Where the lease provision allows subletting subject to the housing provider's reasonable consent or where the lease is silent regarding subletting, the housing provider may condition its consent on the prospective subtenant meeting all of the housing provider's reasonable rental qualification guidelines; provided, that the housing provider furnishes the guidelines to the tenant upon request.