The 1964 Civil Rights Act has laws in place to protect citizens from wrongs done under color of law.
You might find helpful my Legal Guide "What is a civil right?"
Those civil rights laws protect against those who act in violation of constitutional protections under color of law. Talk to your lawyer.
Without a lot more detail, no further observation is possible. There may have been an extension to the hours for investigation.
Good luck to you. You should consult with a local attorney to determine your rights and the best remedy for your situation.
You might find my Legal Guide helpful " What Do I Tell My Lawyer"
God bless you.
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Generally the rule is 24 hours, however there is an exception under many circumstances so long as there is reasonable effort to get you out in front of a judge within 24 hours. Any delay because of processing, finger prints, a large number of people in the system on that given day etc. would all be seen as justifiable reasons for the delay.