New Texas House rules passed on Thursday prevent members of the minority party from holding influential committee chair positions. This change breaks a long-standing tradition in the chamber — and could signal that a contentious legislative session lies ahead.

Although Democrats will be prohibited from chairing the main legislative committees, the chamber voted to expand the powers they can have as vice chairs.

The Texas House voted overwhelmingly Thursday to ban Democrats from holding powerful committee chairmanships, answering years of mounting pressure from leadership and grassroots conservatives to chip away at the minority party’s power in the Capitol.