Blood Pattern Evidence

Fort Lauderdale criminal attorney lecture on lead pattern evidenceThis Week: Fort Lauderdale Criminal Defense Attorney William Moore Talks About Blood Pattern Evidence

Criminal lawyers in Fort Lauderdale that regularly defend homicide cases recognize that patterns created by blood that's been transferred from a human body to another object or surface can be instrumental in defending a murder case. It takes years of criminal defense experience to decipher the meaning that's hidden in this particular type of evidence. Most Criminal Attorneys in Broward, will tell you that there are three basic types of bloodstains—passive, projected, and transferred.

Passive bloodstains are created by a wound that drips or seeps, allowing gravity to pull the droplets downward naturally. When a drop of blood strikes a surface, it's called spatter. The force of impact sometimes causes the spatter to divide into several much smaller droplets called secondary spatter. Some droplets are so tiny that they're barely able to be seen with the naked eye according to Fort Lauderdale Criminal Attorney Moore.

Projected bloodstains occur when blood is forced in a direction other than the downward path caused by the natural pull of gravity.

According to Fort Lauderdale Criminal Defense Attorney Moore, Blood can be propelled away from a body in many ways:

Severed arteries that spurt blood with each beat of the heart; centrifugal force from a moving or flailing lacerated body part; and injuries that force blood away from injured body parts, such as a blow from a hammer or baseball bat.

Transferred bloodstains are caused by a wet, bloody object touching another surface, such as a bloody hand that touches a painted wall or door. The stain that's left on the wall is a transferred stain.

Projected bloodstain from ten milliliters of blood thrown slightly upward onto a smooth vertical wall. The original stain is in the classic teardrop shape because gravity pulls cast-off blood downward.

A victim transfers a bloody handprint—a transfer stain—to a nearby surface.

Experts working for the defense are able to determine the positions of the victim and the killer at the time of impact by establishing the angles of bloodstains. The shapes of the stains are also keys to determining the point of impact. Such evidence tending to contradict the criminal prosecutors evidence can be all it takes to cast reasonable doubt on the State’s case in chief. Blood spatter evidence conversely is also used by the State Attorney’s office in every homicide case where the evidence is properly preserved. The same evidence in the hands of a qualified Fort Lauderdale criminal defense attorney, using equally qualified but different experts can cast quite a spin on the homicide case in general.