US STOCKS-Wall St falls as energy shares decline
* S&P energy index falls with Brent crude oil futures
* July construction spending hits 5 1/2 year high
* Dollar General ups Family Dollar bid
* Digital Ally shares extend rally
* Indexes: Dow off 0.47 pct, S&P off 0.38 pct, Nasdaq up 0.02 pct (Updates to mid-afternoon, adds details on energy shares, updates quote, changes byline)
By Akane Otani
NEW YORK, Sept 2 (Reuters) - U.S. stocks were mostly down on Tuesday, retreating from record highs set the previous month, as energy shares were hit by the fall in crude oil to a 15-month low.
The S&P energy index lost 1.7 percent as Brent crude oil futures fell to their lowest level in 15 months. Noble Corp was the biggest loser among the S&P energy names, falling 3.3 percent, while Ensco PLC fell 3.1 percent.
The dollar's strength was also seen as hurting energy shares as it was partly responsible for oil's decline. Brent crude was down 2.2 percent to $100.46 a barrel on Tuesday. Continuación...