House hopeful Matt Heinz is seeking to knock former Rep. Ann Kirkpatrick off the Democratic primary ballot in Arizona’s 2nd District, funding a lawsuit that alleges she falsely claimed on her nominating papers that she lives in Tucson.

Heinz and Kirkpatrick are both vying for the Tucson-area open seat in southeastern Arizona that GOP Rep. Martha McSally is vacating to run for Senate.

Kirkpatrick has the backing of the Democratic Congressional Campaign Committee and party leaders, but Heinz has criticized her for not hailing from the area. 

She previously represented the 1st District to the north, and moved to Tucson last year shortly before launching her campaign in the 2nd. The lawsuit filed Monday alleges Kirkpatrick actually lives with her husband in Phoenix, rather than in Tucson as she wrote on her nominating papers.

Candidates are not required to live in the district they are running in. But Heinz accused Kirkpatrick of violating a state law that requires candidates to note their actual residence on nominating papers.

“As legal documents, testimony, and other evidence will show, Ann Kirkpatrick engaged in a wide range of fraudulent activities in an attempt to run for Congress in Southern Arizona,” Heinz said in a statement Monday. “This case is not about the fact that Ann Kirkpatrick lives in Phoenix, but about the lies and cover-up she’s used to hide it.”

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Heinz, a physician, is covering all of the legal costs with the lawsuit, his campaign manager Brian Robinson said. The lawsuit was filed in Maricopa County Superior Court on Monday by three voters in the district, one of whom donated to Heinz’s campaign.

Robinson said in an email that those legal costs would be reflected in the next quarterly campaign finance report. He said the costs were unknown as the case is ongoing.

The complaint notes Kirkpatrick listed two addresses in Tucson on her nomination petitions in different time periods: one on Woodspring Road and another on Shannon Road.

Kirkpatrick spokesman Rodd McLeod said in an email that when she and her husband Roger moved to Tucson last year, they moved to an address on Woodspring Road. McLeod said they moved to a larger place on Shannon Road with their son, Sheridan, in the fall of 2017.

McLeod pointed out that Heinz owns a home in the neighboring 3rd District.

“Ann lives in Tucson, in District 2,” he said. “Matt Heinz lives in District 3, so I can only assume he is trying to muddy the waters here by putting forth this false claim.”

Robinson did not deny that Heinz lives in the 3rd District, but said, “The fact that Ann lives in Phoenix and only comes to Southern Arizona for special occasions isn’t the issue. The problem is that she lied about it and then swore in official documents that her lies were the truth.”

The plaintiffs allege Kirkpatrick has not actually resided at the addresses she put down on her nomination papers, in part because she and her husband received an education tax credit on their property taxes for their Phoenix residence.

The complaint includes details such as Kirkpatrick being seen exiting her Phoenix home with a “travel suitcase” when she goes to the Tucson address, and bringing the suitcase with her when she leaves Tucson. The lawsuit also alleges that Kirkpatrick posted twice on social media on May 16 that she was in Southern Arizona, but that she was “observed in Phoenix.”  The complaint does not note the source of the details about her suitcase, or who observed Kirkpatrick in Phoenix on May 16.

Asked how the plaintiffs were aware of those details regarding the suitcase and her whereabouts on May 16, Robinson said evidence mentioned in the complaint “would be presented at trial.”

Heinz and Kirkpatrick are among a handful of Democrats running in the Aug. 28 primary.

The 2nd District represents one of Democrats’ best pickup opportunities this cycle given that Hillary Clinton carried it by 5 points in 2016. Inside Elections with Nathan L. Gonzales rates the race Tilts Democratic.