HARRISBURG — A state lawmaker from Delaware County was charged with theft and related crimes Thursday after a years-long investigation into allegations that she misused campaign and taxpayer funds when seeking reimbursement for expenses.

State Rep. Margo L. Davidson, a Democrat who represents Upper Darby and the surrounding communities, was accused of crimes involving thousands of dollars in expense reimbursements she received between 2015 and 2019.

Prosecutors with the State Attorney General’s Office said Davidson requested overnight reimbursements for time she did not actually spend in Harrisburg. Those reimbursements, known as per diems, are given to most Pennsylvania legislators when they travel to the Capitol from their home districts.

The Attorney General’s Office said Davidson was also reimbursed by taxpayers for expenses that had already been paid for by her campaign. And prosecutors said she failed to disclose what they called “suspicious” campaign expenditures on mandated reports and, at one point during the probe, tried to direct a witness to lie on her behalf.

Davidson, 58, could not be reached for comment. But in a letter to constituents, she said she would resign, adding that she accepted responsibility for her actions, and regretted not “fully participating” in the investigation.

“As I end this chapter, I can say with all assurance that you may have other representatives, but none that will love you more,” she said. “I was a voice and an advocate for underrepresented communities long before I was in the legislature, as I was in it, and I will be a voice for my community long after this day.”

Attorney General Josh Shapiro said in a statement that Davidson waived her preliminary hearing and had paid $6,925 in restitution.

Davidson became the first Black woman elected to the state House from Delaware County more than a decade ago and the first Democrat to win the 164th District in 40 years. She took over the seat held by Republican Mario Civera, the incumbent since 1980.

Her ascendance was the first indication of what would become a major political shift in historically deep-red Delaware County. Ten years later, the former Republican stronghold is now governed by an all-Democrat county council.

“She was dedicated to her constituents and always fought her hardest for those in need in Delaware County,” House Minority Leader Joanna McClinton (D., Philadelphia) said in a statement.

“I am saddened by these charges,” she continued, adding that Davidson’s office will remain open to serve constituents.

As of the close of business Thursday, Davidson had not submitted a letter of resignation to House Speaker Bryan Cutler (R., Lancaster). Cutler can schedule a special election to fill her seat after he receives formal notification.

The allegations against Davidson in many ways showcase how easy it can be to take advantage of Pennsylvania’s lax campaign finance laws, as well as its generous perks for state legislators.

Lawmakers can receive a flat-rate reimbursement, called a per diem, every time they travel more than 50 miles outside their district. The reimbursement amount, which in recent years has ranged between $178 and $200, is meant to cover meals and lodging.

But lawmakers do not have to submit receipts to prove that they spent that much — or any money at all, as prosecutors are alleging in the criminal complaint against Davidson.

According to the criminal complaint, nearly a third of her per diem reimbursements for hotel stays in Harrisburg from 2017 through 2019 were fraudulent. The attorney general alleged that Davidson either had not stayed overnight in Harrisburg, as she had claimed, or she had already been reimbursed for the stay through her campaign account.

Investigators said they were able to pinpoint the fraud through, among other documents, Davidson’s cellphone records, which showed she was placing calls from near her Delaware County district on nights she said she was staying over in Harrisburg.

Investigators also combed through Davidson’s campaign account and reports, which they say showed she sometimes double-dipped when filing expenses, at times charging her campaign for the same hotel stays for which she was receiving a taxpayer-funded per diem.

In other instances, Davidson charged expenses to her campaign account that she either misrepresented or delayed reporting on campaign finance reports, they alleged.

Special Agent Matthew Smith, who signed the criminal complaint against Davidson, said that in October 2015, the lawmaker charged her campaign for a $1,030.51 stay at a Virginia inn. Smith said she didn’t report the expense until a year later, after facing a tough primary challenge.

In August 2017, according to the criminal complaint, Davidson used her campaign credit card for a $600 purchase at a woman’s clothing store but then claimed on campaign finance reports that it was to pay herself back for a loan she had made to her campaign.

In all, Smith said, more than $8,000 in campaign expenses were uncovered that Davidson had not disclosed or falsely reported. Most of the unreported expenditures came in the form of 18 cash withdrawals, he said.

Davidson faces one count each of theft by deception and solicitation to hinder apprehension, as well as election code violations.

A West Philadelphia native, Davidson stirred controversy during her tenure in the state House. In 2018, she drew headlines when she was arrested twice in 12 days for driving and crashing a taxpayer-funded vehicle while her license was suspended. Davidson said she didn’t know her license was suspended until State Police troopers notified her at the site of the second crash. She later pleaded guilty to the charges, which were all summary offenses.

In the General Assembly, her early-on votes to increase restrictions on abortion clinics and in favor of school vouchers drew criticism in Democratic circles and led opponents to cast her as being against progressive values.

She defended her voting record on abortion by pointing to the death of a cousin, who she said was killed in a clinic run by Philadelphia doctor Kermit Gosnell, and she held tightly to the seat. Her name was whispered in some circles ahead of the 2014 state gubernatorial election as a possible candidate for lieutenant governor, though that bid never came to fruition.

Davidson did run in the 2018 race for the then-newly created 5th Congressional District, but she mustered a scant 2,000 votes in the primary won by Mary Gay Scanlon.