He was expelled from the Massachusetts House of Representatives in 1916 for conduct unbecoming a member of the General Court after he collected money from people interested in pending legislation.

[4] During his second term a Senate committee found Foster guilty of indiscreet, imprudent, and injurious conduct, but no action was taken.

[2] On March 1, 1916, State Representative James M. Lyle appeared before the Legislative Committee on Roads and Bridges and accused Foster of collecting money to be used for lobbying a bill compelling the city of Gloucester and the town of Rockport to contribute about $90,000 towards the construction of a new highway through the legislature.

[6] Lyle reiterated his accusation at a session later that afternoon and added that he wanted the matter investigated and that he would present evidence at the proper time.

In its report to the House, the committee wrote that "by collecting money from persons he knew interested in legislation before said General Court... in the manner and under the circumstances set forth in evidence... is guilty of conduct unbecoming a member of the General Court and guilty of such conduct that it demands his expulstion from said body as a member.