Tex. Election Code § 31.017

(a) In a county with a population of more than 4 million, the secretary of state's office may order administrative oversight of a county office administering elections or voter registration in the county if:

(1) an administrative election complaint is filed with the secretary of state by a person who participated in the relevant election as:

(A) a candidate;

(B) a county chair or state chair of a political party;

(C) a presiding judge;

(D) an alternate presiding judge; or

(E) the head of a specific-purpose political committee that supports or opposes a measure;

(2) the secretary of state has provided notice to the county election official with authority over election administration or voter registration under Section 31.018; and

(3) the secretary of state, after conducting an investigation under Section 31.019, has good cause to believe that a recurring pattern of problems with election administration or voter registration exists in the county, including any recurring:

(A) malfunction of voting system equipment that prevents a voter from casting a vote;

(B) carelessness or official misconduct in the distribution of election supplies;

(C) errors in the tabulation of results that would have affected the outcome of an election;

(D) violations of Section 66.053;

(E) discovery of properly executed voted ballots after the canvass of an election that were not counted; or

(F) failure to conduct maintenance activities on the lists of registered voters as required under this code.

(b) The secretary of state shall make a determination on whether to implement administrative oversight under Subsection (a) not later than the 30th day after the earliest of:

(1) the day a response by the county election official with authority over election administration or voter registration is received by the secretary of state under Section 31.018;

(2) the last day the county election official with authority over election administration or voter registration could provide a response to the secretary of state under Section 31.018; or

(3) the day the report on the findings of an investigation is provided to the county election official with authority over election administration or voter registration under Section 31.019.