The Bottom-Up Approach (Year 13 Booklet 5)

Define the bottom-up approach to offender profiling

• Looking at factors of the individual crime scene (situation, specific person) to make conclusions

• Use of systematic analysis of evidence collected at the crime scene to create a unique picture of the offender

Who developed the bottom-up approach and what did they aim to do?

David Canter → Aimed to make process of offending profiling much more scientific

Describe investigative Psychology as a type of bottom-up profiling.

A form of bottom-up profiling matching details from the crime scene with statistical analysis of typical offender behaviour patterns, based on psychological theory

What is meant by interpersonal coherence?

The principle that the way an offender behaves during a crime is consistent with how they behave in their everyday life

What is forensic awareness and how might this be important when identifying an offender?

• Elements of the crime scene that the criminal has committed offences before and been caught

• Helpful because:

  • Has criminal’s DNA

  • Helps narrow down suspects

Define Geographical profiling, and give the name of the person who developed it.

• Kim Rossmo

• A form of bottom-up profiling based on spatial consistency

• An offender’s base and future offence locations can be inferred through the geographical location of previous crimes

What is meant by crime mapping?

Using information from the linked crime scenes to make inferences about the likely base of the offender

What is meant by centre of gravity?

An area containing the base of the offender and the next offending locations (jeopardy surface)

What is Canter’s Circle theory?

The theory that patterns of offending usually form a circle around the offenders residence

What is the difference between a marauder and a commuter?

Marauder → Commits crimes closer to their home base

Commuter → Likely to have travelled a distance away from their usual residence to commit crimes

Provide 3 strengths of the bottom up approach to offender profiling

• Can also predict next crime (when using geographical profiling to identify the jeopardy surface), as well as identifying offender

• More useful than the top-down approach

  • Can be used for a wider range of crimes than the top-down approach

  • More grounded in psychological theory

• Uses a large sample to develop theory

  • Database of thousands of crimes 

  • Confident about theory’s validity

Provide 2 limitations of the bottom up approach to offender profiling

• Rachel Nickell case 

  • Targeted innocent man, Colin Stagg, when using bottom-up approach

  • Didn’t identify actual offender (who was ruled out earlier for being too short), Robert Napper, until over 15 years later

  • Illustrates danger of over-reliance on investigative psychology as people do not always fit into patterns

• Relies on accurate reporting of crimes

  • To effectively use geographical profiling, we need accurate information of all crimes committed 

  • Police forces differ in their accuracy of reporting crimes and only 75% of crimes are reported in the first place

  • Investigative psychology uses data base of solved crimes → What if they were the ones that were easy to solve?

Compare the bottom up approach to the top down approach to offender profiling. Which one is better and why?

• Bottom-up approach is more useful than the top-down approach

  • Can be used for a wider range of crimes than the top-down approach

  • More grounded in psychological theory