As a convicted felon you may not carry any concealed dangerous weapon like a baton etc.
In terms of carrying pocket knives in Illinois the statutes are a bit vague.
Generally, an Illinois resident permitted carrying a pocket knife with a blade up to 3" without qualifying it as a dangerous weapon. However, that is when things may get complicated; having
A knife in your possession while committing a crime, whether or not the knife is being used in the crime, may create grounds for an additional charge of carrying a dangerous weapon which will enhance the original charges related to the alleged crime itself.
Please note that within the city of Chicago the Chicago Municipal Ordinance prohibits possession of any knife with the blade length in excess of 2.5" rather than 3".
Furthermore, switchblades of any kind, defined as being able to be opened without touching the blade by means of a button or release on the handle, are illegal in most states, including Illinois. (720 ILCS 5/24-1,2 States that there is NO limit to a 3" blade length, but rather knives that are either switchblade or ballistic (propelled blade) in possession commits the offense of unlawful use of a weapon. A knife blade that is thrust open by thumb on the blade itself and not on the handle is not in this category and is therefore able to be longer than 3") 720 ILCS 5/Article 33A states that "Armed with a dangerous weapon" means that you are carrying a knife with a blade longer than 3". This in itself is not a crime, but you commit armed violence only when committing a felony with this weapon.
If for any reason you must go to any federal building you must leave the pocket knife otherwise you may face the risk of arrest for carrying a concealed dangerous weapon on federal property, See, 18 USC 930, "Possession of firearms and dangerous weapons in Federal facilities."
For any other questions please consult with a professional attorney before acting on your urge to equip yourself with weapons of any kind.
DISCLAIMER The answer given above by the lawyer serves for educational purposes only and provides general information and a basic understanding of the applicable law. Take notice that the answer above does not create an attorney-client relationship as this website is not intended to provide anyone a specific legal advice. Anyone using the site expressly consents that there is no attorney client privilege between any person and any attorney responding. Further take notice that the site should not be used as a crude substitute for any professional and competent legal advice by a licensed professional attorney in the applicable jurisdiction. The attorney above attempted to provide competent professional information, however, the law and its applications may change frequently and vary greatly from other U.S. jurisdictions and locales. Therefore, any information and materials provided above are general in nature, and may not apply to specific factual and legal circumstances related to oneâ€™s personal legal issues. Contact an experienced criminal defense lawyer admitted to practice in your State under an attorney-client privilege to further receive a competent legal advice before making any important decisions about your particular legal issue. For further inquiries please contact: Attorney Alexander Ivakhnenko 1021 West Adams, 101, Chicago, Illinois 60607 773-562-8602 http://alexanderivakhnenko.com
Convicted felons are prohibited from carrying weapons. In fact convicted felons may not possess or own firearms. A pocket knife falls into a gray area, however, if the police can establish that your carrying it for defense you would be breaking the law. You should consult with an attorney about the possibility of getting your conviction expunged, or at least restoration if your firearm rights.