WASHINGTON (Bloomberg) Former regulators hired by Toyota Motor Corp. helped end at least four federal investigations of unintended acceleration by company vehicles in the last decade, warding off possible recalls, court and government records show.

Christopher Tinto, vice president of regulatory affairs in Toyota's Washington office, and Christopher Santucci, who works for Tinto, helped persuade the National Highway Traffic Safety Administration to end probes, including those of 2002-2003 Toyota Camrys and Solaras, court documents show.

Both men joined Toyota directly from NHTSA, Tinto in 1994 and Santucci in 2003.