Thank you for the opportunity to assist you.
Q) What can I do
That depends on why you want the information. If you simply want the information for the sake of knowledge, try a FOIA request. That's a "Freedom of Information Act" request under state law. Try this page
or this one
for details and a sample request form.
If you were stopped by the police at a checkpoint and charged with a crime or traffic infraction, and you believe the stop was unlawful, you would move to suppress the evidence
of your stop and arrest. Suppression means to ask the judge to keep out certain evidence because it was obtained in violation of your constitutional rights.
Although the US Supreme Court long ago declared
that checkpoints are constitutionally permissible under certain conditions, you are correct that public notice is one of those conditions
Finally, if you were stopped at a checkpoint that you believe violated your civil rights, even if you were not arrested or charged with a crime or infraction, it is possible to sue in federal court for a civil rights violation. The basis for the lawsuit would be that the checkpoint did not meet the requirements set out by the Supreme Court, and thus the stop was in violation of your constitutional protection against unreasonable search and seizure under the fourth amendment.
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