Let’s face it. Not everyone is squeaky clean. This has been true throughout all of human history, and this means your ancestors were just as likely to have done some questionable deeds as anyone else you know. Sometimes, those questionable deeds even resulted in legal action against them, and sometimes, prison time. There have been prisons and jails for just about as long as there have been people. If you know one of your ancestors spent time in prison, or discover through your research that they did, it is always a good idea to look and see if there are any prison records you can use to find out more about them, their family, what landed them there, and what kind of a person they were before, during, and even after their stint in the joint.
A prison record is any record kept by the prison itself or town in which the prison was located, that discusses your ancestor and their stay there. In colonial America, for example, prisons were often informal locations where someone was kept under guard. Often, private houses were used. If there was an actual jail building, it was often in the nearest large town, and dangerous or convicted prisoners were transferred there. During the Quaker persecutions in Salem in the 1660s, for example, the nearest jail to Salem was in Boston and convicted or suspected Quakers were kept in private homes until they could be taken to Boston for a proper incarceration. You won’t find records from these jails, because they were informal. Even the main jails did not keep their own records at this time in American history. However, you will find the prison records of any colonial inmates in the town records and county court records. All information on criminals, suspected criminals, their crimes, and their stays in prison were recorded in these documents, so that is where you want to look.
Other times, your ancestor may have been kept in a military prison. This is usually true for people who committed crimes while serving in the military, or who broke military law in some way. Those who were taken prisoner by the other side during wars were also considered military prisoners. You can find the records of their incarcerations in military records. Usually, the record of the person’s service will include details on incarcerations. The U.S. Department of Veterans’ Affairs also keeps records for more recent incarcerations that have not been archived yet.
If your ancestor was in jail in Europe during Medieval times and was a prisoner due to some infraction that was recognized by the monarch, such as a person who was thrown into the Tower of London for a time, you may find records of their incarceration in old government records of the time. Those who were in prisons in later time periods, after monarchs in Europe lost most of their real power, were often kept in deplorable conditions. But, like anything, their incarceration left a record. You can find these records in the archives of the town in which the prison was located. Most old local prison records, especially in England, are now in archives. You can sometimes find mentions of the crime and the prisoner and why they went to jail in local newspapers.
As for America after colonial times, and for non-military incarcerations, you have several options. It all depends on how long ago the incarceration was, where it was, and who you are to the prisoner.
Records for old incarcerations, usually more than 150 years old, will usually be kept in archives. These are usually state archives, from the state in which the prison was located. If it was a county jail, rather than a prison, you might find the records at the county or town level. Federal prison records will be kept with the federal government, usually at the National Archives in Washington, D.C. You can go there in person, or look up their record collections on their website, and have someone look up the records for you and send them to you, typically for the cost of making copies of the records.
Records that are newer will probably be kept at the actual prison. Some prisons that are no longer used as prisons, but were famous, like Alcatraz, may have their own archives for prisoner records on site. There may even be archive staff to research remotely for you. But, for the most part, the records you are looking for will be kept at the actual prison. If the incarceration was decades ago, you might be able to get the records just by asking. If it is a really recent one, though, but the prisoner is gone on to the next world, you will likely have to prove your relationship to the prisoner. You can do this with the same type of documentation you would use to prove relationships for membership in a lineage society. Birth certificates, death certificates, marriage certificates, and anything else that can connect your name to theirs as a relation may be required.
In some cases, you may need to get a court order from a judge to release the records to you. It all depends on the prison, the prisoner, when the incarceration took place, where it took place, and the reason for it. There may be victims of the crime who still need to be protected, which is one of the most common reasons a more recent prison record may not be released to you until more time has gone by.
Prison records can be extremely useful things in researching your family history. They tell all kinds of things about the prisoner. You will usually get a physical description of them, and maybe even a photo, a record of their crime, their behavior while in prison, their relatives who came to see them, and where (and possibly who) they went with after they were released. Look up these records, and you may open up a whole new door in your genealogy.