Criminals that were nicknamed "Jack"?

During some few moments in my research in some criminals, I was interested by some in them being nicknamed "Jack" something. I have at least four examples of criminals being nicknamed "Jack".

Example number one - The classic Jack the Ripper
Jack the Ripper was an unidentified serial killer active in the largely impoverished areas in and around the Whitechapel district of London in 1888. In both the criminal case files and contemporary journalistic accounts, the killer was called the Whitechapel Murderer and Leather Apron. You can see more information on him on his Wikipedia article.

Example number two - Jack Retalhador
This is a criminal from Brazil which I was surprised to be nicknamed "Jack". I don't see Brazilian criminals very often being nicknamed "Jack".
Story of the Jack Retalhador: In a period of 20 days in 1982, a man nicknamed by police as Jack Retalhador (Jack the Shredder) attacked at least fifteen women in Itajaí, Brazil.

Though none of his victims saw his face, he was described as a black, apparently 18 or 20 years of age and uses a bicycle to attack his victims from behind. He attack his victims one or two razor slashes in the breasts or legs before escaping in his bicycle, laughing. At the time of the investigations, it was determined that the offender only attackd in the city's center, suggesting he was a local resident. Police believes he's mentally challenged. According to police calculations, he had made twenty victims overall. Information from his Amok Wiki article

Example number three - Jack the Stabber
This is a American serial stabber named John Brady, who was nicknamed "Jack the Stabber". He injured 14 to 18 people by stabbing them. Information for John Brady in his Amok Wiki article

Example number five - Wearside Jack
Wearside Jack is the nickname given to John Samuel Humble (8 January 1956 – 30 July 2019), an Englishman who pretended to be the Yorkshire Ripper in a hoax audio recording and several letters in the period 1978–1979.

Humble sent a taped message spoken in a Wearside accent and three letters, taunting the authorities for failing to catch him. The message, recorded on an audio cassette, caused the investigation to be moved away from the West Yorkshire area, home of the real killer, Peter Sutcliffe, and thereby helped to prolong his attacks on women and hindered his potential arrest for eighteen months.

More than 25 years after the event, a fragment from one of Humble's envelopes was traced to him through DNA, and in 2006 Humble was sentenced to eight years in prison for perverting the course of justice. Information for Wearside Jack in his Wikipedia article

I assume they used the name "Jack" to juxtapose "Jane Doe".

Ivan wrote:

I assume they used the name "Jack" to juxtapose "Jane Doe".

John Doe?

Jenn wrote:

Ivan wrote:

I assume they used the name "Jack" to juxtapose "Jane Doe".

John Doe?

Has to be something different from a victim, I guess. It's just a theory after all.

Jack the Stripper, a serial killer Who was active in London during the 1970s.

John Wayne Gacy ( serial Killer) - Tried to fool psychiatrists before his trial into thinking that he had multiple personality disorder and that the personality that committed the murders was Jack Hanley a policeman who Gacy called "Bad Jack"