Forensic psychology needs a sensitive and effective approach, as ethical dilemmas are needed to be dealt with immediately and with care. Psychologists do this by choosing the appropriate approach/perspective, procedures and the outcomes and the effects the conclusions have.
Research into witness appeal Penrod and Cutler (1995) and Ross et al. (1994) can be explained using the social approach due to group norms and conforming to what is “socially” acceptable. Ross et al.(1994) study on child witnesses using protective shields/video link involve cognitive factors such as credibility inflation (automatically assuming guilt of the defendant) or deflation (questioning the reliability of the child witness) on the part of the jury and therefore explains witness appeal through a different approach.
Research into witness appeal involves the use of mock jurors, mock trials and the procedures often involve transcripts or reconstruction. In addition, the samples are psychology undergraduates who tend to have more knowledge into such issues in witness appeal compared with the average person as students use their brains and knowledge more than the average person as they are constantly learning. This means that such research lack ecological validity as we cannot truly generalise such findings to a real courtroom or even understand the level of emotion affecting the jury when a child witness is being protected by a screen/video link, Ross et al. (1994). Transcripts are read by actors and this can also mean the emotions being projected are not realistic to a real life case. The sample are often paid or receive extra credits and this means they are prone to demand characteristics by giving the researcher the result they think is expected by them. In addition, the use of rating scales to measure confidence levels as in Penrod and Cutler (1995) is not realistic to real life court cases and the dilemmas faced by real jurors, therefore, it is low in ecological validity. The usefulness and application of research into witness appeal is important as the findings are used to inform legal teams such as the prosecution and the defence on how to present/ influence their case i.e. whether to present a child with or without protective shields.
Research into witness appeal is also deterministic due to the fact that conclusions reached by studies, for example Penrod and Cutler (1995) shows the more confident a witness is in testifying in court, the more jurors will give a guilty verdict and finally Ross’s study shows how the use of protective shields tend to cause credibility deflation (the jury questions the child’s reliability when hidden behind a shield) and delivers not guilty verdicts. Jurors can be seen as machines who have no independent thoughts or free will when making decisions based on witness appeal. Both studies support situational explanations as the studies show it is how the information is presented. For example in Penrod and Cutler (1995) whether the weapon was brandished clearly or just visible.
In conclusion forensic psychologists are very important as these two studies have shown that every detail in research is important, as the conclusions show that any slight difference can make a big impact in the courtroom for witness appeal.
References:
Penrod, S., & Cutler, B. (1995). Witness confidence and witness accuracy: Assessing their forensic relation. Psychology, Public Policy, and Law, 1 (4), 817-845. doi:10.1037/1076-8971.1.4.817
Ross, D. F., Hopkins, S., Hanson, E., Lindsay, R .C .L., Hazen, K., & Eslinger, T. (1994). The impact of protective shields and vidoeotape testimony on conviction rates in simunlated trial of child sexual abuse. Law and human behavior, 18(5), 553-566. doi:10.1007/BF01499174
psychdout 
When it comes to an eye witness giving evidence in court there are many factors that can contribute to the reliability of the witness: age; occupation; stress; discrimination; event factors; mental state; and many other factors. No matter how small the factor can seem they can all contribute in their own ways effecting the reliability of the witnesses testimony in court. One of the factors that causes the eye witnesses testimonies to be seen as false, inaccurate and misleading is when their memory of events that took place at the scene of the crime become mixed up with other memories (similar memories), or lost altogether. Meaning that an innocent person can be convicted due to mistaken identity and being in the wrong place at the wrong time (thank god for forensics). Even with the help of the cognitive interview, I do not believe that an eye witness’s testimony will be one hundred per cent accurate: leading to my conclusion that an eye witness testimony should only be used in court if it is backed up by other evidence: forensics; CCTV; other eye witness statements and so on.
To help to be sure that the witness is giving an accurate account of the events that took place the police tend to use the cognitive interview technique. The cognitive interview technique is used instead of the standard interview technique as it is believed to result in a thirty per cent improvement of the eyewitness’s recall of the events that they have witnesses, with no increase in the number of incorrect responses (Geiselman et al 1986).
Bartlett (1932) cited in Applying psychology to crime. Hodder and Stoughton: London
Geiselman et al (1986) cited in Applying psychology to crime. Hodder and Stoughton: London