How common is plea bargaining in murder cases.

Factual Questions
1

I know the vast majority of criminal cases in the US are settled with plea bargains, but what about when we talk about murder cases, as opposed to someone caught with pills in his pocket. It seems sometimes the prosecution insists on going to trial to try to get the top count, and sometimes they’ll agree to drop the top count if the defendent agrees to plea and go directlty to jail, no passing go and no lengthy trial and appeals.

Last week Florida let Jarrod Harroll plead guilty in one of those crimes that make you think “this is what the death penalty is for” and get life without parole. And the Bustamonte case, where a 15 year old girl killed a 9 year old to “see what if felt like” they let her plead guilty to murder 2 and get 10 to life as opposed to life without parole for murder 1.

So how often to 1st degree / capital murder cases get plea bargained to a lesser charge or lesser punishment, and how often do they go to trial? It seems I see a lot of murder trials on TruTV (although granted they aren’t going to show a trial of someone caught with pills.
A related question: do females get lighter punsishment for equivalent crimes than males do? Like would the prosecution have accepted a murder 2 plea if Bustamante had been male? The Iowa convenience store killer Michael Swanson, the case of which had some similarities to the Bustamante case, and Doug Stewart in Michigan both got Life without Parole, whereas Bustamante might get out someday, the Blue Eyed Butcher in Texas got only 20 years, Rachel Wade got 27 in the Florida love triangle murder. Had I been on the jury if the Bustamante case had gone to trial I would have felt sorry for her, but still convicted her on the top count. But maybe others would let her off with less; maybe females are viewed as being capable of being rehabilated, or people are reluctant to send a cute woman to jail like they would a 50 year old guy?

2

I recall digging into the numbers once – and must speak from recollection here, since I don’t have time to do it again – but if I recall correctly, all other things being equal, females have an advantage over males when it comes to each stage of the criminal justice system of a factor of two.

That is, a female arrestee is half as likely to be charged for a given crime, half as likely to be convicted, and, if convicted of a capital crime, half as likely to be sentenced to death and half as likely to actually be executed. By the time you add up all those powers of two you can see why executions of female murderers are much rarer than female murderers themselves.

I don’t vouch that the fraction at each stage if 1/2, but I think the expoential nature of the process is accurate.

3

Here is one article suggesting that “many studies” have found that men are sentenced more harshly than women.

Here is a study finding that jurors assess defendants of their own sex more harshly than the opposite sex, while prosecutors and police uniformly assess men more harshly.