From October 2018 to September 2020, Lazaar served as one of five deputy chairpersons of the LREM parliamentary group, under the leadership of chairman Gilles Le Gendre.

[3] In July 2019, she stood as a candidate for the chairmanship of the Committee on Social Affairs; she was defeated in the second round by the incumbent chairwoman, Brigitte Bourguignon.

[4] In addition to her parliamentary work, Lazaar was appointed by Prime Minister Édouard Philippe to chair the National Council against Poverty and Social Exclusion (CNLE) in 2020.

[7] In 2020, Lazaar went against her parliamentary group's majority and abstained from an important vote on a much discussed security bill drafted by her colleagues Alice Thourot and Jean-Michel Fauvergue that helped, among other measures, curtail the filming of police forces.

[8][9] In July 2019, Lazaar voted in favor of the French ratification of the European Union’s Comprehensive Economic and Trade Agreement (CETA) with Canada.