D.C. Code § 1-1321
At the request of the proprietor the Surveyor shall examine whether the lots or parcels into which any square or lot may be subdivided as provided in § 1-1320 agree in dimensions with the whole of the square or lot so intended to be subdivided, and whether the dimensions expressed on the plat of subdivision be the true dimensions of the parts so expressed; and whether said lots or parcels conform to the general orders of the Council of the District of Columbia made under existing law or under authority of § 1-1313; and if upon such examination he shall find the plat correct he shall certify the same under his hand and seal to the Mayor with such remarks as appear to him necessary; but no such plat or subdivision shall be admitted to record in the Office of the Surveyor without an order to that effect, indorsed thereon by said Mayor.
D.C. Code § 1-1321