Lawyers for the Colorado theater shooting suspect filed at least six new constitutional challenges to the state's death penalty laws on Monday.

In the new motions made public on Tuesday, lawyers for James Holmes argue that the death penalty has been arbitrarily imposed in Colorado, is not a deterrent, is used so rarely that it's unconstitutional and that its use is cruel and usual.

"Imposition of the death penalty is rare, unusual, freakish, and inconsistently applied throughout the State of Colorado," defense lawyers wrote in a motion.

Another motion asked that victims not be allowed to testify when the jury is deciding punishment and that opponents of the death penalty be allowed to sit on Holmes' jury.

One of the motions also cites a 2009 study by the University of Colorado titled, "Do Executions Lower Homicide Rates? The Views of Leading Criminologists," published in the Journal of Criminal Law and Criminology that found, "94 percent agreed that there was little empirical evidence to support the deterrent effect of the death penalty."

Colorado currently has three men sitting on death row and has only executed one person since the death penalty was declared unconstitutional in 1972. The death row inmates -- Nathan Dunlap, Sir Owens and Robert Ray -- were all sentenced in Arapahoe County.

Holmes has pleaded not guilty by reason of insanity to charges that he opened fire on a Colorado theater, killing 12 people and injuring 70 more in July 2012.

Also on HuffPost:

Loading Slideshow...
  • Tom Sullivan , holds a photograph of his son, Alex Sullivan, as he pleads with the media to help him find his son, outside Gateway High School on Friday, July 20, 2012 in Aurora, Colo. Alex Sullivan, was celebrating his 27th birthday by attending midnight premiere of the Batman movie Friday night. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • A woman cries outside Gateway High School where witness were brought for questioning after a gunman opened fire at a midnight premiere of The Dark Knight Rises Batman movie Friday, July 20, 2012 in Aurora, Colo. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Tom Sullivan, center, embraces family members outside Gateway High School where he has been searching frantically for his son Alex Sullivan who celebrated his 27th birthday by going to see "The Dark Knight Rises," movie where a gunman opened fire Friday, July 20, 2012, in Aurora, Colo. (Photo credit: AP Photo/Barry Gutierrez)

  • Eyewitness Chandler Brannon, 25, sits outside Gateway High School where witnesses were brought for questioning after a shooting at a movie theater showing the Batman movie "The Dark Knight Rises," Friday, July 20, 2012 in Aurora. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • A small group prays outside Gateway High School where witness were brought for questioning Friday, July 20, 2012 in Aurora, Colo. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Family and friends wait outside Gateway High School where witnesses were brought for questioning after a shooting at a movie theater showing the Batman movie "The Dark Knight Rises," Friday, July 20, 2012 in Aurora, Colo. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Eyewitness Jacob Stevens, 18, hugs his mother Tammi Stevens after being interview by police outside Gateway High School where witnesses were brought for questioning Friday, July 20, 2012 in Aurora, Colo. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Eyewitness Isaiah Bow hugs his mother Shamecca Davis after being questioned by police outside Gateway High School where witnesses were brought in, Friday, July 20, 2012 in Aurora, Colo. After leaving the theater Bow went back in to find his girlfriend. "I didn't want to leave her in there. But she's ok now," Bow said. A gunman wearing a gas mask set off an unknown gas and fired into the crowded movie theater killing 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Emma Goos, 19, hugs her mother, Judy Goos, outside Gateway High School where witnesses were brought for questioning Friday, July 20, 2012, in Aurora, Colo. Emma was in the third row of the theater of the new Batman movie when the shooter entered. She helped apply pressure to a man's head who was injured. (Photo credit: AP Photo/Barry Gutierrez)

  • Police cars in front of the Century 16 theater in Aurora, Colorado where a gunman opened fire during the opening of the new Batman movie "The Dark Knight Rises" killing at least 15 people and wounding 50 others on the morning of July 20, 2012. The shooting suspect in custody after at least 12 people were shot dead and around 50 were wounded at a movie screening in the United States has been identified as 24-year-old James Holmes, US media said Friday. Television networks cited the FBI as saying that Holmes, from the town of Aurora, Colorado, scene of the midnight shooting at a screening of the Batman movie "The Dark Knight Rises," did not appear to have any known terrorism connections. (Photo credit: AFP PHOTO/JONATHAN CASTNER JONATHAN CASTNER/AFP/GettyImages)

  • Police tape cordons off the parking area around the Century 16 movie theater in Aurora, Colorado, July 20, 2012 where a gunman opened fire during the showing of the new Batman movie. At least 12 people were killed and around 50 wounded in the cinema shooting. (Photo credit: AFP PHOTO JONATHAN CASTNERJONATHAN CASTNER/AFP/GettyImages)

  • Police cars in front of the Century 16 theater in Aurora, Colorado where a gunman opened fire during the opening of the new Batman movie "The Dark Knight Rises" killing at least 15 people and wounding 50 others on the morning of July 20, 2012. The shooting suspect in custody after at least 12 people were shot dead and around 40 were wounded at a movie screening in the United States has been identified as 24-year-old James Holmes, US media said Friday. Television networks cited the FBI as saying that Holmes, from the town of Aurora, Colorado, scene of the midnight shooting at a screening of the Batman movie "The Dark Knight Rises," did not appear to have any known terrorism connections. (Photo credit: AFP PHOTO/JONATHAN CASTNERJONATHAN CASTNER/AFP/GettyImages)

  • Police cars in front of the Century 16 theater in Aurora, Colorado where a gunman opened fire during the opening of the new Batman movie "The Dark Knight Rises" killing at least 15 people and wounding 50 others on the morning of July 20, 2012. The shooting suspect in custody after at least 12 people were shot dead and around 50 were wounded at a movie screening in the United States has been identified as 24-year-old James Holmes, US media said Friday. Television networks cited the FBI as saying that Holmes, from the town of Aurora, Colorado, scene of the midnight shooting at a screening of the Batman movie "The Dark Knight Rises," did not appear to have any known terrorism connections. (Photo credit: AFP PHOTO/JONATHAN CASTNERJONATHAN CASTNER/AFP/GettyImages)

  • Police cars are seen in the parking area around the Century 16 movie theater in Aurora, Colorado, July 20, 2012 where a gunman opened fire during the showing of the new Batman movie. At least 12 people were killed and around 50 wounded in the cinema shooting. (Photo credit: AFP PHOTO JONATHAN CASTNERJONATHAN CASTNER/AFP/GettyImages)

  • Police use a video camera to look inside an apartment where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. (Photo credit: AP Photo/Ed Andrieski)

  • Police break out a window of an apartment where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. (Photo credit: AP Photo/Ed Andrieski)

  • Shamecca Davis hugs her son Isaiah Bow, who was an eye witness to the shooting, outside Gateway High School where witness were brought for questioning Friday, July 20, 2012 in Denver. After leaving the theater Bow went back in to find his girlfriend. " I didn't want to leave her in there. But she's ok now," Bow said. A gunman wearing a gas mask set off an unknown gas and fired into a crowded movie theater at a midnight opening of the Batman movie "The Dark Knight Rises," killing at least 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • Judy Goos, second from left, hugs her daughters friend, Isaiah Bow, 20, while eye witnesses Emma Goos, 19, left, and Terrell Wallin, 20, right, gather outside Gateway High School where witness were brought for questioning Friday, July 20, 2012 in Denver. A gunman wearing a gas mask set off an unknown gas and fired into a crowded movie theater at a midnight opening of the Batman movie "The Dark Knight Rises," killing at least 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • A SWAT team officer stands watch near an apartment house where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 14 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. (Photo credit: AP Photo/Ed Andrieski)

  • Police gather near an apartment house where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. (Photo credit: AP Photo/Ed Andrieski)

  • A SWAT team officer stands watch near an apartment house where the suspect in a shooting at a movie theatre lived in Aurora, Colo., Friday, July 20, 2012. As many as 12 people were killed and 50 injured at a shooting at the Century 16 movie theatre early Friday during the showing of the latest Batman movie. (Photo credit: AP Photo/Ed Andrieski)

  • Jacob Stevens, 18, hugs his mother Tammi Stevens after being interview by police outside Gateway High School where witness were brought for questioning after a shooting at a movie theater, Friday, July 20, 2012 in Denver. A gunman wearing a gas mask set off an unknown gas and fired into a crowded movie theater at a midnight opening of the Batman movie "The Dark Knight Rises," killing at least 12 people and injuring at least 50 others, authorities said. (Photo credit: AP Photo/Barry Gutierrez)

  • (Credit: Sky News)

  • (Credit: Sky News)

  • (Credit: Sky News)

  • (Credit: Sky News)

  • Police are pictured outside of a Century 16 movie theatre where as many as 12 people were killed and many injured at a shooting during the showing of a movie at the in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • Police are pictured outside of a Century 16 movie theatre where as many as 12 people were killed and many injured at a shooting during the showing of a movie at the in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • Aurora Police Chief Daniel Oates talks to media at Aurora Mall where as many as 12 people were killed and many injured at a shooting at the Century 16 movie theatre in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • Aurora Police Chief Daniel Oates talks to media at the Aurora Mall where as many as 14 people were killed and many injured at a shooting at the Century 16 movie theatre in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • Police are pictured outside of a Century 16 movie theatre where as many as 12 people were killed and many injured at a shooting during the showing of a movie at the in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • Police are pictured outside of a Century 16 movie theatre where as many as 12 people were killed and many injured at a shooting during the showing of a movie at the in Aurora, Colo., Friday, July 20, 2012. (Photo credit: AP Photo/Ed Andrieski)

  • People gather outside the Century 16 movie theatre in Aurora, Colo., at the scene of a mass shooting early Friday morning, July 20, 2012. Police Chief Dan Oates says 12 people are dead following the shooting at the suburban Denver movie theater. He says 50 others were injured when gunfire erupted early Friday at the Aurora theater. Oates says a gunman appeared at the front of one of the Century 16 theaters. <em>Photo Credit: Karl Gehring, <a href="http://www.huffingtonpost.com/news/exposure/" target="_hplink">Denver Post</a>. </em> / AP

  • (Photo credit: 7NewsMorning/Twitter)

  • (Photo credit: 7NewsMorning/Twitter)

  • (Photo credit: Faunte Thompson/Twitter)

  • (Photo credit: 7NewsMorning/Twitter)

  • (Photo credit: Brandon Rittiman/Twitter)

  • (Photo credit: 7NewsMorning/Twitter)

  • (Photo credit: Jakeob Bame/Twitter)