6.3 Evidence Handling & Exclusionary Rule

6.3 Evidence Handling & Exclusionary Rule

Primary Legal Objective: Physical, digital, and testimonial evidence collected during a criminal investigation must be legally admissible in court and physically uncompromised. Understanding Pennsylvania's Exclusionary Rule, the doctrines governing derivative evidence, chain of custody protocols, and statutory rules of evidence is essential for law enforcement officers to secure convictions that survive appellate review.

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1. The Exclusionary Rule in PA (Commonwealth v. Edmunds, 1991)

The Exclusionary Rule is a constitutional doctrine mandating that evidence obtained through illegal police conduct (searches or seizures violating constitutional rights) is inadmissible in court against the accused.

Rejection of the Federal "Good Faith" Exception

In federal jurisprudence, United States v. Leon, 468 U.S. 897 (1984) created a "good faith" exception, allowing evidence seized under a defective search warrant to be admitted if officers acted in objectively reasonable reliance on a warrant issued by a magistrate.

However, in the landmark decision Commonwealth v. Edmunds, 586 A.2d 887 (Pa. 1991), the Pennsylvania Supreme Court explicitly REJECTED the federal good faith exception under Article I, Section 8 of the Pennsylvania Constitution.

Philosophical Distinction: Privacy vs. Deterrence

The PA Supreme Court explained that while the federal Fourth Amendment exclusionary rule is designed strictly to deter police misconduct, Article I, Section 8 of the Pennsylvania Constitution exists to protect individual privacy rights and judicial integrity. Consequently, in Pennsylvania, if a search warrant lacks probable cause or suffers from a fatal constitutional defect, the evidence MUST be suppressed, regardless of how reasonably or blamelessly the officers acted.

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2. Fruit of the Poisonous Tree Doctrine & Exceptions

Established federally in Wong Sun v. United States, 371 U.S. 471 (1963), the Fruit of the Poisonous Tree Doctrine holds that evidence derived from an initial unlawful police action (the "poisonous tree") is also tainted and inadmissible as "fruit" of that primary illegality.

However, Pennsylvania law recognizes three distinct exceptions where derivative evidence may still be admitted if the Commonwealth satisfies its burden of proof:

1. Independent Source Doctrine (Commonwealth v. Melendez)

Evidence obtained following an unlawful search or seizure remains admissible if police can prove it was independently discovered through a truly separate, lawful investigative channel that was completely untainted by the initial illegal police conduct.

2. Inevitable Discovery Exception

Under the Inevitable Discovery Exception, tainted evidence is admissible if the Commonwealth proves by a preponderance of the evidence that the items would have inevitably been discovered through routine, standardized, lawful police procedures already underway, independent of the constitutional violation.

3. Attenuation of Taint

Tainted derivative evidence may be admitted if the causal connection between the primary illegal police conduct and the ultimate discovery of evidence has become so attenuated (weakened) as to purge the original taint. Courts evaluate: (a) temporal proximity between illegality and discovery; (b) presence of intervening circumstances; and (c) the purpose and flagrancy of official misconduct.

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3. Chain of Custody & Evidence Integrity

The Chain of Custody is the complete, unbroken, chronological record documenting the seizure, custody, control, transfer, analysis, and disposition of physical and electronic evidence from collection through courtroom presentation.

Key Protocols for Preserving Integrity

1. Seizure & Marking: Immediately upon collection, the seizing officer must mark evidence with unique identifiers (case number, item number, date, time, officer initials).
2. Packaging: Evidence must be placed in appropriate, tamper-evident containers (e.g., breathable paper bags for biological material, anti-static bags for digital devices, approved canisters for arson evidence).
3. Property Room Management: Evidence must be logged into a secure police property repository with restricted access, logged entries, and climate-controlled storage.
4. Log Book Maintenance: Every transfer of custody—whether to a crime lab technician, court exhibit room, or prosecutor—must be recorded in an official evidence log with dates, times, and signatures of both releasing and receiving individuals.

Legal Effect of Gaps

An unbroken chain of custody guarantees that evidence presented at trial is authentic and in substantially the same condition as when seized (Pa.R.E. 901). Minor gaps in the chain generally go to the weight of the evidence assigned by the jury, but major gaps or unexplainable losses can result in complete judicial exclusion of the evidence.

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4. Pennsylvania Rules of Evidence (Pa.R.E.) Basics

Police officers must understand basic evidence rules to ensure testimony and physical items survive courtroom objections under the Pennsylvania Rules of Evidence (Pa.R.E.).

Relevancy (Pa.R.E. 401, 402, 403)

• Relevancy Standard (Rule 401): Evidence is relevant if it has any tendency to make a fact of consequence in determining the action more or less probable than it would be without the evidence.
• Rule 403 Balancing Test: Relevant evidence may be excluded if its probative value is substantially outweighed by the danger of unfair prejudice, confusing the issues, misleading the jury, undue delay, or needlessly presenting cumulative evidence.

Hearsay Definition & Exceptions (Pa.R.E. 801–804)

• Hearsay Definition (Rule 801): An out-of-court statement offered in court by a witness to prove the truth of the matter asserted. Hearsay is generally inadmissible (Rule 802) because the out-of-court declarant is not under oath or subject to cross-examination.
• Key Hearsay Exceptions (Pa.R.E. 803 & 804):
  1. Excited Utterance (Rule 803(2)): A statement relating to a startling event or condition made while the declarant was under the stress of excitement caused by the event.
  2. Present Sense Impression (Rule 803(1)): A statement describing or explaining an event or condition made while or immediately after perceiving it.
  3. Business Records Exception (Rule 803(6)): Records of regularly conducted activity kept in the ordinary course of business (e.g., police CAD logs, hospital toxicology reports).
  4. Statements Against Interest (Rule 804(b)(3)): A statement made by an unavailable declarant that was so contrary to their penal or financial interest that a reasonable person would not have made it unless true.

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Overview of Evidence Rules & Exclusionary Doctrines