The Prince George's County Council yesterday defeated a motion that citizens groups said could have resulted in the construction of a new highway from Rosecroft Raceway to Charles County.

The motion, introduced by council member Gerard McDonough, would have allowed the council to reconsider its votes on the construction or elimination of certain roads in the Henson Creek master plan in the southern part of the county. Witnesses testified at the work session that it could have resulted in a decision to construct a highway that the council previously voted against.

The highway, the citizens said, would have helped McDonough's brother, John McDonough, a lawyer, obtain a zoning change for a client's development. The change was previously denied on the grounds that the area did not have adequate roads.

Gerard McDonough denied that he introduced the motion to help his brother. He said he was concerned about increasing the housing supply in the county. "Every day, people my age are screaming and yelling about how I can't buy a house," said McDonough.

But a zoning lawyer in the same zoning firm as John McDonough, Russell Shipley, acknowledged that such a highway would be "helpful" in his law firm's efforts to get zoning approved for the development, known as Mattawoman.

The proposed development, to be built on a site at the junction of Rtes. 301 and 5, was rejected by the council years ago, but has been reintroduced for consideration. It would consist of 2,000 acres of single-family homes, office buildings and shopping facilities.