The latest on developments in financial markets (All times local):
Stocks are closing modestly lower, having recouped much of a steep loss from earlier in the day after a former adviser to the White House pleaded guilty to lying to the FBI.
News that former national security adviser Michael Flynn would co-operate with the probe into Russian meddling in the U.S. presidential election initially sent the market stumbling, but investors were encouraged after Senate Republicans signalled they have enough votes to push forward on a tax overhaul bill.
Technology and industrial stocks accounted for much of the decline. Energy companies led the gainers.
The Standard & Poor's 500 index 5 points, or 0.2 per cent, to 2,641. The Dow Jones industrials lost 40 points, or 0.2 per cent, to 24,231. The Nasdaq composite gave back 26 points, or 0.4 per cent, to 6,847.
Stocks veered sharply lower after ex-Trump adviser Michael Flynn pleaded guilty to making false statements to the FBI.
Flynn, a former national security adviser, also said Friday he would co-operate with special counsel Robert Mueller's wide-ranging investigation.
Investors worried that the developments could spell trouble for the White House and its legislative agenda, including a massive tax overhaul that has been making progress in the Senate.
Small-company stocks, which would benefit the most from corporate tax cuts, fell far more than the rest of the market.
The Russell 2000 index plunged 2.2 per cent.
The Standard & Poor's 500, a broad measure of large companies, fell 28 points, or 1.1 per cent, to 2,619, erasing its gain from Thursday.
The Dow Jones industrials lost 237 points, or 1 per cent, to 24,036.
Stocks are off to a mixed start following a big jump the day before that sent the Dow Jones industrial average through 24,000 points for the first time.
Technology shares, an investor favourite since the beginning of the year, slipped in early trading Friday.
Qualcomm was off 1.1 per cent after Bloomberg News reported that Broadcom, a rival chipmaker, won't make a new offer for the company until next year.
Meal kit maker Blue Apron was up 5 per cent after naming a new CEO. The company has struggled since its initial public offering in June.
The Standard & Poor's 500 index fell 2 points, or 0.1 per cent, to 2,645.
The Dow Jones industrial average lost 25 points, or 0.1 per cent, to 24,248. The Nasdaq composite fell 15 points, or 0.2 per cent, to 6,858.