As of a couple of years ago, 2% of male prisoners were claiming to be transwomen.

As I recall it, the 2% figure was given by the UK Ministry of Justice and pertained to male prisoners in England and Wales. Not everywhere.

But more to the point, the UK figures are not relevant to this story, which is specifically about prisoners in the USA.

The TIMs in the women's prison are not allowed to mix freely with the women, and have guards walking around with them.

This is not definitely not true of the USA. Janiah Monroe, known as Andre Patterson by the Illinois Department of Corrections, has been accused of sexually assaulting "more than one" of the female inmates in the women's prison he was transferred to, Logan. On the the very first day he was allowed in with the general population in the women's prison, he raped a female inmate.

Monroe, a delicate flower who strangled to death with his bare hands one of his male cellmates in the male prison where he was previously held, has had a "turbulent" since being transferred to the women's prison, the Logan warden has testified:

"Multiple tickets, serious infractions, previous PREA (Prison Rape Elimination Act) allegations, inappropriate sexual behavior and a confirmed investigation that substantiated sexual misconduct," Austin [the Logan warden] said in his July deposition. "Her actions here at the facility, I think with her history, to me it is very concerning."

Also:

Monroe, 30, has been locked up since 2005, when she was charged with shooting two people outside a barbershop. In 2006, she strangled her cellmate in the Cook County jail. Department of Corrections records show she's serving time for 11 felonies, including second degree murder, attempted murder, aggravated battery, aggravated battery involving a government employee, three counts of aggravated battery involving a peace officer, two counts of aggravated attempted arson, damage to government property and bringing contraband into a penal institution.

https://www.illinoistimes.com/springfield/transgender-inmate-accused-of-rape/Content?oid=11867999

https://www.womenarehuman.com/transgender-felon-who-killed-male-cellmate-with-bare-hands-now-accused-of-raping-female-inmate-janiah-monroe-ne-andre-patterson/

https://news.wttw.com/2020/02/19/lawsuit-female-prisoner-says-she-was-raped-transgender-inmate

There are many, many women's prisons in the US. In addition to the federal prison system - which at the moment operates 29 different prisons for federal female convicts around the US - each state and territory in the US has its own correctional system and its own prisons (though sometimes states work together to house prisoners from one state in facilities of another state.) In addition, within each state individual counties and municipalities in the US have their own correctional institutions that are separate from the federal and state ones.

Of the approximately 231,000 women currently incarcerated in the US, the bulk are split between state prisons and local jails (99,000 and 101,000 respectively); 16,000 are in federal prisons and jails; and the remainder are in immigration detention or other kinds of facilities, such as youth detention centers, jails on US Indian territory, or military prisons.

https://www.prisonpolicy.org/reports/pie2019women.html

I have not read every state statute or state prison policy on this topic, but the laws that have been passed in states so far - Connecticut and now California - mandating prison placement based on convicts' and inmates' "gender identities" do not stipulate that TIMs placed in, or transferred to, female prisons are to be kept apart from the female prisoners. So far, such segregation has not been the policy or practice of any prison or jail in the US that has put rules in place allowing TIMs to be housed behind bars with women.

On the contrary, the entire argument made on behalf of such men is that they must not only be allowed to "live as" women in women's facilities, but they must be allowed to live amongst and in close quarters with women, and treated exactly like any female prisoner would be treated, coz these men's mental health depends on having their "gender identities" "affirmed" and "validated" by female inmates and everyone who works in female corrections. The way the USA's "equal protection" clause and the rules regarding "cruel and unusual punishment" are interpreted by lawmakers, courts and prison authorities in the US, TIMs and their advocates would immediately file lawsuits challenging any attempts to segregate "male women" from "female women" under the new laws and rules that allow prison placement to be based on gender identity, not sex.

However, on a case-by-case basis, prisoners in the US can be kept apart from other prisoners if correctional authorities can prove they pose a danger to themselves or others, or for punishment for breaking prison rules. For example, since committing the sex assaults against female prisoners and all the other serious infractions of prison rules at Logan, Monroe apparently has been held in isolation.

After Monroe committed the verified sexual assault of a female prisoner, and the alleged assaults on others, Illinois correctional officials initially decided to send him back to male prison. However, while in transit, the Illinois governor stepped in and ordered that Monroe be returned immediately to the female prison. As it happens, the Illinois governor is JB Pritzker, brother of former Obama Commerce Secretary Penny Pritzker and cousin of Jennifer Pritzker, a late-in-life transitioning heterosexual AGP father and former military man who is one of the biggest funders of orgs pushing trans ideology and the medical transing of children.

As for the UK: it's not true that in UK TIMs placed in women's prisons are "not allowed to mix freely with the women, and have guards walking around with them." There have been several high-profile cases in the UK where male prisoners who ID as trans such as "Karen White" have sexually assaulted female prisoners or had supposedly consensual sexual relations with them, as well as many cases that have not been publicized. If these men were kept apart from the females and always accompanied by guards, it's unlikely they could have committed these acts - unless, that is, the guards were in on it with the TIMs.

https://www.dailymail.co.uk/news/article-8303753/Transgender-inmates-carried-seven-sex-attacks-women-jail.html

A few years ago, a special wing for TIMs opened up HMP Downview, a women's prison in the UK, and at that time the UK government did publicly state that the male inmates in that one particular wing would be kept separate from the female inmates in that facility. However, this wing was not set up for all TIMs in women's prisons. It was specifically established solely to house

Transgender women holding Gender Recognition Certificates who have been assessed as presenting a high risk of harm to other women in custody… where the risk cannot safely be managed on normal location within the Women’s Estate.

Other TIMs not deemed as presenting as high a risk to female prisoners are still being placed in with the general population in UK women's prisons.

Also, as it's turned out, the especially dangerous TIMs placed in the special wing for them in Downview have not been kept separate from the female prisoners as the government initially promised. These particularly dangerous male prisoners bunk and eat separately, but they are still allowed access to the gym and exercise facilities, classes, the library, support groups, faith groups and services, trainings etc where they can mingle with and have access to female prisoners.

A female inmate at Downview says that shortly after the TIM wing opened, one of the male "transgender" inmates in the trans wing sexually assaulted her. BTW, this particular TIM has "convictions for serious sexual offenses."

The unnamed female inmate is currently challenging the UK practice of placing men who ID as trans in Downview and all other women's prisons under any circumstances in an judicial review challenging the legality of the MOJ's policy and seeking to find out on what basis the MOJ came up with the policy in the first place. (The JR has been delayed coz on the first day of proceedings, MOJ said it could not respond to questions the plaintiff and court asked or provide evidence due to ministerial "confidentiality" - which led to a entirely different set of separate legal issues that have to be worked out before the JR can continue.)

But significantly, there's been nothing reported to say the MOJ, Downview authorities or the accused TIM inmate have disputed or challenged whether this TIM inmate did indeed sexually assault the female plaintiff as she has claimed. That and the fact that she has been granted permission for the JR against the MOJ suggests the assault did actually occur.

https://www.thetimes.co.uk/article/transgender-prison-wing-failed-its-inmates-phqkp0qff

https://www.womenarehuman.com/following-alleged-sexual-assault-female-inmate-challenges-legality-of-placing-violent-males-in-womens-prisons/

More information here: https://www.keep-prisons-single-sex.org.uk/