He unsuccessfully contested the Walthamstow West constituency at the 1922 and 1923 general elections, before winning the seat at the 1924 general election, narrowly defeating the sitting Labour MP Valentine McEntee. During the 1924-29 parliament which was dominated by a Conservative majority, Crawfurd worked closely with a group of radical Liberal MPs that included: William Wedgwood Benn, Percy Harris, Joseph Kenworthy and Frank Briant to provide opposition to the government.
He ran for the Walthamstow West constituency in the 1922 and 1923 general elections without success, but ultimately won the seat in the 1924 general election, narrowly defeating Labour MP Valentine McEntee. During his time in parliament from 1924 to 1929, Crawfurd worked with a group of liberal MPs who were critical of the Conservative government, including William Wedgwood Benn, Percy Harris, Joseph Kenworthy, and Frank Briant.