Personnel in Criminal Investigations

Ever wondered who's involved when a crime occurs? Several key professionals work together to solve criminal cases.

Crime Scene Investigators (CSIs) collect and process evidence from crime scenes, ensuring it remains uncontaminated. Their responsibilities include wearing protective clothing, photographing evidence, recovering physical and biological materials (like fingerprints or DNA), and properly documenting everything. CSIs must maintain evidence integrity, as contaminated evidence becomes inadmissible in court.

Police officers are typically first at crime scenes and play crucial roles in securing the area and preserving evidence. During "The Golden Hour" (the period immediately after a crime's discovery), officers must act quickly to take initial statements while memories are fresh. They also safeguard the public and secure the crime scene to prevent contamination.

⚠️ Police officers have been criticized in some cases for failing to properly secure crime scenes or for not investigating certain crimes thoroughly, as seen in the Stephen Lawrence murder investigation.

Their thoroughness in these initial stages can make or break a case. For instance, in Ann Ming's case, her daughter's body was found under a bathtub, but it took police 80 days to discover it despite it being in the house the whole time - highlighting how critical proper investigation procedures are.

Forensic Scientists and Prosecution Services

Forensic scientists apply scientific knowledge to analyze crime scene evidence. They examine samples like blood or other bodily fluids to extract DNA and compare it with samples from suspects. These specialists often focus on specific areas such as DNA analysis, arson investigation, toxicology, or forensic anthropology.

Though powerful, forensic evidence isn't foolproof. In 2011, Adam Scott spent five months in custody after his DNA sample was accidentally mixed up with genetic material from a rape case—a stark reminder that even scientific evidence can be compromised.

The Crown Prosecution Service (CPS) is an independent organization operating across England and Wales that makes critical decisions about criminal cases. They:

• Advise police on investigations
• Decide whether to prosecute cases
• Determine appropriate charges
• Prepare cases for court

The CPS has significantly improved the justice system. Before its establishment, police were responsible for investigating, charging, and prosecuting cases, which created potential bias. By separating these roles, the CPS provides independent assessment of evidence.

💡 The CPS can reject police requests to prosecute if they believe there's insufficient evidence, helping prevent unjust prosecutions.

However, the CPS faces challenges including overwhelming caseloads and staff shortages, which can lead to errors in reviewing evidence. Such mistakes were evident in the Damilola Taylor murder case, where the CPS failed to properly check a witness account before trial.

Pathologists and Evidence Collection Techniques

Pathologists are medical doctors specializing in studying disease causes and death. During post-mortems (autopsies), they examine bodies for signs of foul play, inspect internal organs, and collect tissue samples for lab analysis. With starting salaries around £89,233, pathologists are highly specialized and well-compensated.

While pathologists provide crucial scientific evidence about cause and time of death, there are only about 35 Home Office registered forensic pathologists in England and Wales. This shortage can delay investigations. Even these experts can make mistakes—as in Sally Clark's case, where pathologist Alan Williams failed to disclose important bacterial infection evidence that could have explained her children's deaths.

DNA analysis is among the most powerful techniques in criminal investigations. Its strengths include:

• High reliability due to each person's unique DNA
• Ability to solve cold cases years later
• Helping prove both guilt and innocence

The Melanie Road case demonstrates DNA's power—her 1984 murder remained unsolved until 2016 when DNA evidence connected Christopher Hampton to the crime through his daughter's DNA sample.

🔍 DNA evidence has limitations too: it's expensive, requires the suspect's DNA to be in a database for comparison, and can be invalidated by cross-contamination.

Surveillance techniques can be either covert (hidden) or overt (visible) and provide permanent images of crimes occurring. While effective for street crimes like robbery and theft, covert surveillance risks infringing on civil liberties, as seen in the Colin Stagg case where police used an undercover female officer to form a relationship with him to gather evidence.

Offender Profiling and Eyewitness Testimony

Offender profiling helps identify suspects by analyzing crime patterns and characteristics. Several approaches exist:

Geographical profiling examines locations and timing of offences to determine where offenders might live or work. It's based on two principles:

• The least effort principle: offenders choose targets closer to home
• The buffer zone: offenders avoid committing crimes too close to home

David Canter identified two offending patterns: "marauders" who commit crimes near their base, and "commuters" who travel far from home to offend.

Investigative Psychology profiling infers offender characteristics from their actions during crimes. It uses the offender consistency principle—that criminal behaviour reflects non-criminal behaviour patterns.

Typological Profiling analyzes crime scenes to understand offender characteristics. Developed by the FBI in the 1970s, it helps predict future offender behaviour. However, it can suffer from the "Barnum Effect"—when vague descriptions seem accurate but could apply to many people.

⚠️ Profiling is only effective if all crimes are committed by the same person. If the offender changes their methods or some crimes are missed, the profile might be inaccurate.

Eyewitness Testimony can be compelling evidence as it provides detailed firsthand accounts of crimes. However, it relies on memory, which can be unreliable under stress. The Ronald Cotton case highlights this issue—he spent over 10 years in prison based on mistaken eyewitness identification before being exonerated.

These techniques, while valuable, must be used carefully as part of a broader investigation strategy to ensure accuracy and fairness.

Processing Physical Evidence

Proper handling of physical evidence is crucial for criminal investigations. Without it, cases can fall apart in court.

Blood evidence must be collected on sterile material if liquid, and within 28 hours should reach a forensics lab. Dried blood requires the entire article to be properly containerized and labeled. Blood can reveal crucial DNA information about suspects.

Fingerprints provide unique identification evidence. Latent prints can be revealed using UV light, powder, or chemical agents. Prints can also be found in soft materials where pressure was applied. The collection typically involves swabbing with magnesium powder sometimes mixed with super glue substances.

Hair samples often found on clothing should be wrapped in paper and submitted to labs. Even small fragments can reveal information about race and body origin. Similarly, bite marks, often seen in sexual assault cases, can be photographed and cast to compare with suspects' dental impressions.

💡 All physical evidence must be handled with extreme care to prevent contamination. CSIs typically wear protective clothing including masks, hooded scene suits, overshoes, and multiple pairs of gloves.

When physical evidence is properly collected and preserved, it can be decisive in solving cases. The Melanie Road murder case demonstrates this—evidence preserved from 1984 eventually identified Christopher Hampton as the killer through DNA matching with his daughter 32 years later.

However, improper handling can lead to contamination, making evidence inadmissible or unreliable. This happened in Adam Scott's case, where DNA sample mix-up led to his wrongful imprisonment for rape in 2011-12.

Rights in Criminal Investigations

When someone is arrested, they have specific rights designed to ensure fair treatment. Understanding these rights is essential for both suspects and law enforcement.

Suspects' rights include:

• Being told why they're being arrested
• Being held for only 24-36 hours (extendable to 96 hours with magistrate approval)
• Remaining silent during questioning (though this could later harm their defense)
• Access to free legal advice and having a solicitor present during questioning
• Protection from forced confessions

When police stop and search someone, they must have legitimate grounds to do so. They can request individuals to account for their actions, presence in an area, or possession of certain items. There are 19 different legal powers allowing police to search for items like drugs, firearms, or stolen goods.

Victims' rights are equally important and include:

• Regular updates on case progress
• Information about arrests, charges, and sentencing
• Opportunity to apply for compensation
• Special assistance when giving evidence if vulnerable
• Making a victim personal statement explaining the crime's impact

🔔 Vulnerable victims of serious crimes like attempted murder, domestic abuse, sexual offences, hate crime, or terrorism are entitled to faster information and specialist support.

Witnesses are protected by the Witness Charter, which ensures they have a main contact throughout the process, receive information about court procedures, and have safe waiting areas separate from defense witnesses. Vulnerable or intimidated witnesses can give evidence behind screens, via video link, or with communication specialists to help them.

These rights aim to balance the need for effective criminal investigations with protecting individuals from unfair treatment.

Prosecuting Suspects

The decision to prosecute a suspect involves careful consideration by the Crown Prosecution Service (CPS).

The CPS plays a crucial charging role by advising police during investigations and independently assessing evidence before deciding whether to prosecute. They apply specific tests outlined in the Code for Crown Prosecutors:

The Evidential Test asks:

• Is there enough evidence for a conviction?
• Is the evidence reliable and believable?
• Can the evidence be used in court?

The Public Interest Test considers:

• The seriousness of the offence (more serious crimes are more likely to be prosecuted)
• Circumstances of the victim and harm done (prosecution is more likely if victims are vulnerable)
• Whether the defendant held a position of trust
• If the offence was motivated by discrimination

In urgent situations, the CPS can apply The Threshold Test to make an immediate charging decision even without all evidence being available. This typically happens when suspects present a substantial bail risk.

💡 The CPS's independent assessment helps prevent biased prosecutions that might occur if police handled both investigation and prosecution.

Criminal offences are categorized by severity:

• Indictable offences are the most serious (murder, rape, robbery) and must be tried in Crown Court
• Triable Either Way offences (theft, burglary, assault causing actual bodily harm) can be tried in either court
• Summary offences (minor motoring offences, minor assaults) are usually tried in Magistrates' Court

These distinctions determine where cases are heard and the maximum possible sentences upon conviction.

The Trial Process

Understanding how courts operate helps us see how justice is delivered through the legal system.

Roles in court include:

• Prosecution: Represented by the CPS, they present facts in an equal way
• Defence: Represents the defendant (who doesn't have to prove innocence)
• Judge: Determines appropriate sentences after hearing both sides
• Magistrates: Decide guilt or innocence in Magistrates' Court and can send cases to Crown Court if their sentencing powers (limited to six months) aren't sufficient
• Jury: In Crown Court, 12 citizens consider evidence and deliver the verdict

The bail system allows temporary release of accused persons while awaiting trial. Under the Bail Act 1976, magistrates can grant either:

• Unconditional bail: No conditions except attending court as required
• Conditional bail: May include reporting to police stations, avoiding contact with certain people, or following curfews

📝 Most criminal cases begin in Magistrates' Court, with more serious cases passed to Crown Court. Crown Court cases include a jury of 12 members of the public who decide on guilt or innocence.

Before trial, defendants must plead either guilty or not guilty. A guilty plea often leads to immediate sentencing or adjournment for reports. For not guilty pleas, magistrates must make decisions about reports, legal aid, and bail before proceeding.

Plea bargaining involves agreements between prosecutors and defendants where guilty pleas are exchanged for concessions. Critics argue this can pressure defendants and undermine their right to fair trials.

The appeals process depends on the court type and whether appealing conviction or sentence. Those convicted in Magistrates' Court have automatic appeal rights, while Crown Court verdicts require permission to appeal within 28 days, and only on grounds that the conviction was "unsafe."

Evidence Rules and Influences

Evidence must follow specific rules to be admissible in court, often summarized by the acronym "HAD."

Hearsay evidence refers to statements made outside court that witnesses want to rely on. Usually inadmissible, exceptions exist when:

• The witness is unavailable due to anxiety, fear, or death
• The court believes using the evidence serves justice

For evidence to be admissible and relevant, it must be:

• Credible: The court must believe witnesses are truthful
• Accurate: Expert evidence must be supported by scientific consensus
• Properly obtained: Evidence gained illegally may be inadmissible

Evidence of bad character (previous convictions, cautions, racism) is only admitted under specific circumstances, such as showing a defendant's tendency to lie.

Disclosure of evidence requires prosecutors to notify the accused of all evidence they'll use in court. The prosecution must also disclose unused material that might undermine their case or assist the defense. In 2017, Liam Allen's rape trial was paused when undisclosed evidence showed the accuser had pursued him for casual intimacy.

⚠️ Failure to disclose evidence has caused numerous cases to be dropped in recent years, highlighting serious flaws in the system.

Several factors influence case outcomes:

• Juries can ensure defendants are judged by peers but may be swayed by emotions
• Evidence quality can make or break cases, though forensic errors do occur
• Media coverage can create bias but also helps inform the public
• Witness testimony can be compelling but is subject to memory limitations
• Expert witnesses provide specialized knowledge but can make errors, as in Sally Clark's case
• Politics can influence sentencing trends, especially after high-profile incidents like the 2011 London riots

Lay People in the Justice System

Our justice system relies heavily on ordinary citizens taking on important legal roles. These "lay people" help ensure that justice reflects community values.

Juries have been part of the legal system for over 1,000 years. Their main role is as "deciders of fact" who determine guilt or innocence based on evidence presented. Jurors must be:

• Aged 18-75
• UK residents for at least 5 years since age 13
• On the electoral roll
• Not mentally disordered

People are disqualified from jury service if they've received a life sentence, been imprisoned for five years, are currently on bail, or can't understand English well.

🔔 Juries are founded on the individual's right to a fair trial by the just determination of their peers—a principle dating back to the Magna Carta of 1215.

Magistrates are unpaid volunteers who hear about 90% of criminal cases. They determine verdicts and sentences in summary trials and handle various administrative duties. To qualify, candidates must:

• Be aged 18-65
• Live or work in their assigned area
• Commit to at least 26 half-days per year
• Possess six essential characteristics: good character, social awareness, communication skills, maturity, sound judgment, and commitment

The jury system's strengths include representing society's cross-section, ensuring justice is delivered legally, and providing balanced perspective from ordinary citizens. However, weaknesses include potential bias from media or personal beliefs, difficulties understanding complex legal issues, and the risk of "jury nullification" where juries acquit despite clear evidence.

Similarly, magistrates offer cost-effective justice with local insight, but they're sometimes criticized for being less representative than juries, potentially "case hardened," or inconsistent in sentencing across different regions.