Generally speaking, "marked money" is usually photocopied by the police before it is used as "buy money." The failure to recover the buy money could help with the defense. You should be discussing this matter with your attorney. Knowing all of the facts and circumstances puts him/her in the best position to answer your questions.
There are numerous reasons why police allow a drug transaction to take place without making an immediate arrest: They may be protecting the identity of an informant or undercover officer. They may be getting ready to execute a search warrant or they may be trying to move higher up the food chain and catch a bigger fish in the criminal enterprise. It is not grounds for getting the case thrown out but depending on the other facts involved, might help your defense. The fact that marked money was not recovered is helpful but if there is a reasonable explanation why it wasn't recovered, (such as no immediate arrest) jurors tend to overlook this fact.
Instead of trying to play defense attorney, I suggest you hire a skilled criminal defense attorney who is trained and experienced in breaking these cases down and planning the best defense possible.
I am a former Deputy Bureau Chief with the Kings County DA’s Office and adjunct professor at John Jay College of Criminal Justice, with over 15 years experience specializing in criminal law cases. I offer free in-person, phone and video consultations.
All answers are for information purposes only. Answering this question or any future questions does not form any attorney-client relationship. Be mindful, that answers are limited by the limited facts presented by the questioner and are not meant to take the place of competent legal advice by an attorney fully informed of all the facts surrounding your case. However, be aware that nothing posted in a public forum such as this can be deemed confidential or privileged communication. For a privileged private consultation, contact me at 212-385-8600 or via my website www.reasonabledoubtny.com
Marked money is not registered. The actual term is "pre-recorded buy money." The police photo copy it before they use it. The police do not have to make an arrest right away. There are many reasons not to. If the buy was inside an apartment or home, the police usually do 2 controlled buys with a CI before applying for a search warrant to show the CI is reliable. Another reason is if the police make an immediate arrest, they will burn the CI, which they don't want to do.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 385-8015 or via email at Eric@RothsteinLawNY.com. The above answer is for informational purposes only and not meant as legal advice.