Two wardens implicated in the spectacular escape of a prisoner in Cologne were cleared of charges on Friday.

The case made headlines last year when a convicted rapist - Peter B., now 59, - escaped his handlers close to the city's most popular tourist site, the Cologne cathedral. During a visit to a popular local brewery nearby, the guards allowed the inmate to use the restroom unaccompanied. Peter B. used the opportunity to flee through the bathroom window.

The prison officers didn't realize something was wrong until Peter B. failed to return to their table after 30 minutes. To make matters worse, they didn't report his escape for another half an hour, giving the inmate a one-hour head start on the police.

He was nabbed three days later, roughly 20 kilometers (12 miles) south of Cologne in the town of Brühl. However, his capture was far from the end of the story for the two officers - 40 and 52 years old, respectively - who were charged with aiding his escape, which carries a sentence of up to five years in prison.

Addressing the court on Friday, the Cologne judge ruled that, while the two men had been "negligent," they were not guilty of the charges brought against them by the state prosecutors of North-Rhine Westphalia (NRW).

Prisoner outings - what's normal, what's not

The German penal system includes outings in its rehabilitation strategy for inmates. For prisoners serving a longer sentence  - like Peter B., who was incarcerated in Aachen in 1999 - an outing is granted at least four times a year under the supervision of two wardens. Prisoners can be denied the privilege if they pose a flight risk or might commit a crime.

According to NRW's Justice Ministry, individual prisons determine which security measures are taken during excursions.

Outings generally take place over several hours, but there isn't a "typical" excursion prescribed to inmates, Andreas Schürholz - a spokesman for the Ver.di union chapter of Germany's penal system - told DW in an email.

The German penal code views these measures as a necessary step toward helping prisoners maintain life management skills. They are also aimed at motivating prisoners to prepare for full reintegration into society.

The point is to "get an impression of life outside the prison walls," NRW Justice Ministry spokesman Marcus Strunk told DW. Visits can range from a doctor's appointment to buying clothing, or in Peter B.'s case, stopping for lunch.

Whatever outing prisoners are granted, in no case would a prisoner under preventative detention, like Peter B., be left unaccompanied.

Prison break Germany

Germany's prison system - which has roughly 63,000 prisoners or 0.76 for every 1,000 inhabitants - has come under increasing scrutiny for a serious security mishaps.

Escapes on the level of Peter B.'s toilet break last year are rare. However, the prison escapes - while also not an everyday event - do make the news from time to time. Many of them have occurred in Germany's most populous state, NRW, home to roughly one-fourth of the prison population.

In May, a 22-year-old who was being held on suspicion of predatory extortion crawled under a delivery truck, grabbing on to its undercarriage as it drove away. Had protocol been followed, he should've been caught by his officer, who was supposed to conduct a headcount of the group unloading the truck, - or at the very latest - the gatekeepers, who only checked the inside.

A year before that, a 43-year-old prisoner near Bonn chose a container of wood chips as his ticket to freedom, while a year before that, an inmate in Bochum walked out of jail using a visitor's pass. The 26-year-old later turned up nine months later in Amsterdam.

Also contributing to security problems is the deterioration of old facilities and lack of personnel, as well as increased difficulty in stamping out the smuggling of cell phones (sometimes by drone), drugs and money.

While each state grapples with these changes, the NRW parliament is currently reviewing a draft bill for ankle bracelets that would - at least - prevent a repeat of last year's toilet break in Cologne.