Atlanta police officers stand guard outside the WWE Survivor Series, a professional wrestling event in Atlanta, Georgia November 22, 2015. REUTERS/Tami Chappell In Georgia, if you get a traffic ticket and you can't afford to pay in full up front, you are put on misdemeanor probation until the fine is paid.

And in Georgia, as in at least four other states, that probation is typically managed by a for-profit company.

These companies — more than 20 in Georgia alone — make tens of millions of dollars each year by tacking additional fees onto probationers’ repayment plans with the threat of jail if they fall behind.

Now a modest change in state law has driven the state’s largest for-profit probation provider out of the business, according to court emails.

Sentinel Offender Services, which collected almost $4 million in fees in the first three quarters of last year, according to state data, pulled out of its contract at the Atlanta Municipal Court as of Jan. 1 and sold its remaining contracts — more than 50 statewide — in February.

“As it now stands, the concept of the probationer as the sole source of revenue for a probation service entity has become politically and fiscally untenable,” the company wrote in a June 2016 proposal to Atlanta Municipal Court administrators.

Private probation companies bill themselves as “offender-funded” services: rather than spending taxpayer money to staff and run a probation office, courts contract with one of these companies at no cost. The companies set up shop, collect probationers’ court fines to forward to the county and then charge additional fees that serve as revenue for them. These fees can at times double, or more than double, the original fine.

The practice dates back to 2000, when the Georgia legislature passed a law that explicitly allowed it. It began to come under fire around 2012, when a string of lawsuits began to argue that the scheme essentially criminalized poverty by putting people on probation, and, at times, jailing them, solely because of their inability to pay. Sentinel and other companies were also sued for requiring drug tests — and making probationers pay for them — even when a judge had not ordered it. The companies have paid out millionsin settlements, and several lawsuits are ongoing.

In this Nov. 20, 2012 photo, pedestrians pass a sign near the entrance for the Atlanta BeltLine in Atlanta. Associated Press/David Goldman

With pressure mounting, in 2015 the Georgia legislature passed HB 310, which said companies could not charge more than three months of fees to people who were only on probation because they could not pay a fine. It also added some protections, such as a special hearing, before someone can be jailed for failure to pay. Gov. Nathan Deal signed the bill into law in May of that year.

Within the year, Sentinel began looking for other ways to make money, according to a cache of emails between Sentinel officials and Atlanta Municipal Court staff, obtained by the Southern Center for Human Rights through an open records request and shared with The Marshall Project.

“The passage of House Bill 310…established guidelines that have made the supervision of pay-only probationers extremely difficult,” wrote Sentinel Chief Business Development Officer Mark Contestabile in June 2016. “While Sentinel agrees that some reforms were needed, we are not completely satisfied with the current circumstance and believe further changes need to be introduced.”

According to the emails, Sentinel sought to move from an “offender-funded” model into a “public/private partnership.” In that model, courts — not probationers — would begin paying $25 per month for each person on probation. Sentinel suggested the court increase the fines it charged to boost revenue.

Reached by phone, Mark Contestabile declined to comment on the emails. Detailed questions sent to Contestabile and to Tim Lewis, whose signature in the emails identified him as VP of Georgia Services, were not answered.

When this public/private partnership proposal went nowhere, Sentinel changed tack and appears to have tried to increase other fees that were not prohibited by HB 310. In September, Sentinel officials submitted to the court a standing order, requesting the chief judge sign it. The Atlanta Municipal Court would not provide The Marshall Project with a copy of the order, but an October 2016 message suggests the company was seeking permission to charge a “credit card and admin fee.”

When the judge declined to sign the order, Sentinel officials began to pull out of the private probation business. In October, Contestabile emailed the courtto say that the “reduction in probation supervision fees has resulted in a program that is financially no longer feasible to operate.”

Robert Couse-Baker A court spokeswoman did not respond to requests for comment.

The company pulled out of Atlanta in December and then in February sold the more than 50 other contracts it had in courts elsewhere throughout the state to CSRA Probation Services. With more than $2 million in fees in the first three quarters of 2016, CSRA was then the state’s second most profitable private probation company, after Sentinel. Contestabile confirmed that Sentinel has “departed that sector,” referring to the private probation business, but declined to comment further.

This is a mixed victory to critics of private probation. On one hand, reforms such as HB 310 and lawsuits with big payouts means that running these operations is “becoming a closer call for companies,” says Phil Telfeyan, whose organization Equal Justice Under Law brought a 2015 lawsuitaccusing a private probation provider in Tennessee of extortion and racketeering. “This feeds into the calculus of their profit margins and liability.”

On the other hand, “you don’t end the problem, you simply displace one company with another,” says Alexandra Natapoff, a law professor at Loyola Law School who has studied fees and fines in the criminal justice system. “It’s risky to count on profit reduction as a method of criminal justice reform. You don’t necessarily get better justice. What you may get are more enterprising and less risk-averse entrepreneurs.”

Twenty-nine private probation companies continue to operate in Georgia. In the first three quarters of last year they collected almost $18 million in fees, according to figures obtained by the Southern Center for Human Rights.

Judicial Correctional Services submitted the winning bid to replace Sentinel in Atlanta. Calls and emails to the company were not returned.

In their bid, the company assured the court, “All services listed are offender funded and will be offered at no cost to the City.”