The law does not limit your consideration of mitigating factors to those that can be articulated in advance. Therefore, you may consider during your deliberations any other factor or factors in Dzhokhar Tsarnaev’s background, record, character, or any other circumstances of the offense that mitigate against imposition of a death sentence

Unlike aggravating factors which must be proven beyond a reasonable doubt, mitigating factors must be proven by the lesser standard of a preponderance of the evidence.

It's not a mathematical weighing. Each juror can assign whatever weight he or she wants to any mitigating factor. One mitigating factor can outweigh all aggravating factors, and the jurors need not be unanimous in the weight or importance they give to any mitigating factor.

In order to return a verdict of death on any count, the jury must first find for that count that Tsarnaev was over 18 at the time the act was committed, and that Government proved at least one gateway factor and one statutory aggravating factor beyond a reasonable doubt.

There are also six non-statutory aggravating factors, but the jury can't consider them unless it has already found the government proved one gateway factor and one statutory aggravating factor beyond a reasonable doubt. Also, the gateway factors are not part of the weighing process -- they are just a threshold the government must meet for the jury to even consider a death sentence.

Here are the mitigating factors:

• 1. Tsarnaev was 19 years old at the time of the offenses.
• 2. Tsarnaev had no prior history of violent behavior
• 3. Dzhokhar Tsarnaev acted under the influence of his older brother
• 4. Whether because of Tamerlan's age, size, aggressiveness, domineering personality,
  privileged status in the family, traditional authority as the eldest brother, or other
  reasons, Dzhokhar Tsarnaev was particularly susceptible to his older brother's influence
• 5. Dzhokhar Tsarnaev's brother Tamerlan planned, led, and directed the Marathon
  bombing.
• 6. Dzhokbar Tsarnaev's brother Tamerlan was the person who shot and killed Officer Sean Collier.
• 7. Dzhokhar Tsarnaev would not have committed the crimes but for his older brother Tamerlan.
• 8. Dzhokhar Tsarnaev's teachers in elementary school, middle school, and high school knew him to be hardworking, kind, respectful and considerate
• 9.His friends in high school and college knew him to be thoughtful, caring and respectful of the rights and feelings of others.
• 10. His teachers and friends still care for him
• 11.Tsarnaev's aunts and cousins love and care for him.
• 12. Mental illness and brain damage disabled Dzhokhar Tsarnaev's father.
• 13. Dzhokhar Tsarnaev was deprived of needed stability and guidance during his adolescence by his father's mental illness and brain damage.
• 14. Dzhokhar Tsarnaev's father's illness and disability made Tamerlan the dominant male figure in Dzhokhar's life.
• 15. Dzhokhar Tsarnaev was deprived of the stability and guidance he needed during his adolescence due to his mother's emotional volatility and religious [illegible]
• 16. Dzhokhar Tsarnaev's mother facilitated his brother’s radicalization
• 17. Tamerlan Tsarnaev became radicalized first, and then encouraged his brother to follow him.
• 18. Dzhokhar Tsarnaev's parents’ return to Russia in 2012 made Tamerlan the dominant adult male in Dzhokar Tsarnaev’s life.
• 19. He is highly unlikely to commit, incite or facilitate any acts of violence in the future while serving a life without release sentence in federal custody
• 20. The government has the power to severely restrict his communication with the outside world
• 21. He has expressed sorrow and remorse for what he did and the suffering he caused

The jury does not have to be unanimous in its finding of mitigating factors.

Recall that your vote as a jury need not be unanimous with regard to each question in this section. A finding with respect to a mitigating factor may be made by one or more of the members of the jury, and any member of the jury who finds the existence of a mitigating factor may consider such a factor established in making his or her individual determination of whether or not a sentence of death shall be imposed, regardless of the number of other jurors who agree that the factor has been established.

For each death eligible count for which it has found at least one gateway factor and one statutory aggravating factor, the jury then considers non-statutory aggravating factors, and then weighs the statutory and non-statutory factors proven beyond a reasonable doubt against the mitigating factors found to exist and arrives at one of several options: Unanimous agreement for death on every count; unanimous agreement for death on some counts (it must specify which ones); unanimous agreement for life without release on all counts; or it can't unanimously decide on life or death (in which case a sentence to life without release will be imposed.) For death on any capital count, the jury must consider

whether the aggravating factor or factors found to exist for each count sufficiently outweigh the mitigating factor or factors found for that count to justify a sentence of death, or in the absence of a mitigating factor, whether the aggravating factor or factors alone is sufficient to justify a sentence of death.

The final jury instructions are not yet on the court's docket. I'll be curious to see how much of what the defense proposed is included and which of its proposed instructions were rejected.

I think the defense put on a strong case for life. I will be very surprised if the jury unanimously votes for death on any count.