[3] In 2009, when Jackson Lago was removed from office by the Brazilian Superior Electoral Court and the Supreme Federal Court decided to instate election runner-up Roseana Sarney, Weverton remained on Jackson's side at the Palácio dos Leões,[4] the seat of government, until the final decision about his mandate in a move of resistance that referred to itself as Balaiada, a reference to a people's revolt in the 19th century against the monopoly of landowners.

He also updated to the Ministry of Labor and Employment, in 2009, and invited by the national president of the PDT, Carlos Lupi, to integrate his team as a special assessor.

Weverton is a member of the national executive council of the PDT and presides over its state party in Maranhão.

He positioned himself as being against the 2017 labor reforms put forth by the Temer government, due to the pro-labor stances of the PDT.

Weverton introduced various amendments to social security reforms,[9] among them to maintain the current rules for retirement for rural laborers and their families, which would stipulate to have proven 15 years of effective individual contributions in taxes.

In June 2018, he voted against government reforms to liberalize gun laws to more freely allow the carrying and possession of firearms in Brazil.

[11] Weverton had introduced the main emphasis to the projects surrounding the law that outlined the 10 measures against corruption, which added that magistrates and members of the Public Ministry respond to crimes of abuse of authority when they acted with conduct incompatible to their position.

[12] This emphasis, the most controversial of all changes made, and was considered by some an attempt to intimidate the prosecutors of Operation Car Wash,[13] was approved with 313 votes in favor, 132 against the measure, and 5 that were absent.

[12] Weverton has been investigated for embezzlement and corruption, for his supposed involvement with the funneling of funds from the Labor ministry by way of irregular contracting with NGOs.

[14] In an interview to the local press, meanwhile, the person that succeeded him as secretary had declared that the decision to eventually stop the project was political in nature.

He is also being investigated in three separate lawsuits for administrative impropriety, made by prosecutors at the federal level and in Maranhão, one in which he had supposedly been the beneficiary of the usage of private jets paid for by public entities in the Labor Ministry during the time in which he was secretary.

[17] He has used the media platforms he has leased out to as a venue to showcase his actions during his time as federal deputy,[18][19] as well as to the benefit of politicians he has aligned himself with, such as former São Luís mayor Edivaldo Holanda Júnior.

[20] The financial transactions referring to the leasing out of these companies, as well as a possible selling of the conglomerate, have been intermediated by businessman Willer Tomaz de Souza, who had been imprisoned due to being implicated in Operation Car Wash on 18 May 2017.