Why? The main reason is that Lucius failed to retrieve the prophecy from the Ministry of Magic, put that on top of all the other times Lucius failed, and it leads to him losing any clout he once carried within the
Lucius Malfoy's failure at the Department of Mysteries combined with accidentally destroying part of Voldemort's soul with the diary of Tom Riddle resulted in his loss of any standing with the Dark Lord. Some believed that he was safer in Azkaban than being free. Lucius was sentenced to life imprisonment in Azkaban.
After the events in the Department of Mysteries, Voldemort mainly blamed Lucius for the failure. He blamed Lucius because Lucius had been the commander of Voldemort's small task force, even though Dumbledore himself had entered the fray.
Narcissa's greatest moment, however, was when she chose to betray Voldemort in Harry Potter and the Deathly Hallows. Not knowing whether Draco was alive or dead, Narcissa chose to lie to the Dark Lord rather than risk losing her son.
He selected Lucius wand to further punish him for failing to acquire the prophecy. And Lucius wand was consumed and destroyed by the golden fire Harry's wand created when it spun and cast on it's own. This is why, shortly afterward, Voldemort, still airborn, is demanding Selwyns wand.
The Malfoys are able to avoid serving time in Azkaban, as they provide evidence that helps the Ministry track down the Death Eaters who had fled after the war. It is also probable that, since Narcissa's lie to Voldemort saved Harry's life, the family is pardoned for their crimes.
Because he lost the favor of Voldemort who held infinite more power and control over everything including his family and most importantly his dear son who was seemingly sent on a suicide mission due to Lucius' failures.
Draco Malfoy's mother Narcissa was cold, cunning and devoted to the Dark Lord. But she was also a mother, which meant she was willing to risk everything to make sure her son was safe. When Harry survived Voldemort's Killing Curse for the second time, Narcissa pretended he was dead so she could get to Draco.
Malfoy is far crueler and snobbish than his son, believing in blood purity and wizarding supremacy. Lucius is a genuinely dangerous presence in Chamber of Secrets; he even tries to kill Harry in the Hogwarts hallway.
Draco's refusal to reveal Harry's identity to Bellatrix was not because he liked him. It was because he believed that Harry was the only chance they had at defeating Voldemort.
Lucius Malfoy was one of the powerful death eater who avoided Azkaban but still didn't try to search Voldemort. Lucius Malfoy failed to retrieve Prophecy from kids. A perfectly crafted plan which led Harry out of Hogwarts without any protection of the Order/Dumbledore, completely ruined.
Lucius Malfoy did nothing to dispel this hateful impression and was a fully signed up supporter of pure-blood supremacy. In fact, he was in Lord Voldemort's closest circle as a Death Eater. He despised Muggles, Muggle-borns, those he saw as blood traitors and tried to instil those values in his family.
The plain answer is no.
In the movie, yes, Lucius Malfoy did start to say the incantation for the Killing Curse before he got stopped by Dobby. However, Jason Isaacs, the actor playing him, stated in an interview that he just said the first spell that came into his head, which happened to be Avada Kedavra.
Lucius is a known practitioner of the Dark Arts with his wand, including Unforgivable Curses. He attempted to perform the Killing Curse on Harry in Harry Potter and the Chamber of Secrets, but his once-enslaved house-elf Dobby interfered and repelled him.
Harry Potter's wand shot a stream of golden flames at Lord Voldemort of its own accord during the Battle of the Seven Potters. The spell was powerful enough to break Lucius Malfoy's wand.
Specifically, Draco was jealous of Harry. It was easy to miss because Draco didn't often show his emotions, modelling himself on his cold, confident, calculating father, but J.K. Rowling has confirmed that a lot of his enmity towards Harry stemmed from envy.
After Voldemort's death in 1998, Delphi became Salazar Slytherin's last known heir.
According to the author, J.K. Rowling: No, the Malfoys weaseled their way out of trouble (again) due to the fact that they colluded (albeit out of self-interest) with Harry at the end of the battle. Lucius did something similar after the first Wizarding War in Britain.
She asked him because if Draco was still alive, she had something to fight for. She had a reason to lie to Voldemort. If Draco is alive, she needs to get into the school to see him and protect him, and helping Harry feign death was the easiest way to do that. But if Draco was already dead, she wouldn't have bothered.
Rowling commented that "The moment Draco got what he thought he wanted, to become a Death Eater, and given a mission by Lord Voldemort, as he did in Harry Potter and the Half-Blood Prince, reality finally hit him" because his dream was "so very different".
I've always suspected Molly's lethal spell was a particularly well-placed and powerful stunner that stops Bellatrix's heart, which is consistent with the description of her death: Molly's curse soared beneath Bellatrix's outstretched arm and hit her squarely in the chest, directly over her heart.
The psychopath: Bellatrix Lestrange. It's impossible to discuss scary death-eaters without including Bellatrix Lestrange. Everything about her is horrible, from her obsessive allegiance to Voldemort to her gleeful wickedness and fondness for inflicting pain on others.
Strongest: Bellatrix Lestrange
Everyone's favorite Death Eater was also arguably Voldemort's most talented. Although her dueling skills were of the most impressive of all of her colleagues, her unyielding support of the Dark Lord is what gave her edge. She wasn't afraid to put her life on the line for Voldemort.